Chapter 13
| Excel Templates to accompany Operations Management, Twelfth Edition | |||||||
| created by Lee Tangedahl | |||||||
| Copyright ©2015 McGraw-Hill Education. All rights reserved. | |||||||
| Chapter Thirteen - Inventory Management | |||||||
| Example 10 | |||||||
| Templates: | ABC Classification System (B) | Example 11a | |||||
| Basic Economic Order Quantity (EOQ) Model (B) | Example 11b | ||||||
| Economic Production Quantity (EPQ) Model (B) | Example 12 | ||||||
| Quantity Discounts (B) | Example 13 | ||||||
| Reorder Point (ROP) with EOQ Ordering (B) | Example 14 | ||||||
| Fixed Order Interval Model (B) | Example 15 | ||||||
| Single Period Model (B) | |||||||
| Solved Problems: | Solved Problem 1 | ||||||
| (B) - includes Basic template | Solved Problem 2 | ||||||
| Solved Problem 3 | |||||||
| Lecture Suggestions | Solved Problem 4 | ||||||
| Solved Problem 5 | |||||||
| Examples: | Example 1 | Solved Problem 6 | |||||
| Example 2 | Solved Problem 7 | ||||||
| Example 3 | Solved Problem 8 | ||||||
| Example 4 | |||||||
| Example 5 | Problems: | Problems 1-10 | |||||
| Example 6 | Problems 11-20 | ||||||
| Example 7 | Problems 21-28 | ||||||
| Example 8 | Problems 31-39 | ||||||
| Example 9 | Problems 40-44 | ||||||
| See the Inventory Management tutorial for a demonstration of the these templates. | |||||||
| See Instructions template for complete instructions. |
ABC
| ABC Classification System | Basic | |||
| <Back | ||||
| Dollar Amount | Number of Items | |||
| Class | Total | Percent | Total | Percent |
| A | 40,000 | 52.69% | 1 | 10.00% |
| B | 31,000 | 40.84% | 3 | 30.00% |
| C | 4,910 | 6.47% | 6 | 60.00% |
| Enter lower limit for dollar amount: | ||||
| A | 40,000 | B | 9,000 | |
| Unit | Dollar | |||
| Item | Usage | Cost | Amount | Class |
| 1 | 25 | 360 | 9,000 | B |
| 2 | 10 | 70 | 700 | C |
| 3 | 24 | 500 | 12,000 | B |
| 4 | 15 | 100 | 1,500 | C |
| 5 | 7 | 70 | 490 | C |
| 6 | 10 | 1,000 | 10,000 | B |
| 7 | 2 | 210 | 420 | C |
| 8 | 10 | 4,000 | 40,000 | A |
| 9 | 80 | 10 | 800 | C |
| 10 | 5 | 200 | 1,000 | C |
| Basic Template: | You can simply copy the basic template below and paste into another worksheet. | |||
| ^Top | If you also copy the graph you will have to fix the cell references in the graph | |||
| (right-click on the graph, click Select Data..., and Edit the Series values for each series). | ||||
| ABC Classification System | ||||
| Dollar Amount | Number of Items | |||
| Class | Total | Percent | Total | Percent |
| A | 4,000,000 | 52.69% | 1 | 10.00% |
| B | 3,100,000 | 4083.78% | 3 | 30.00% |
| C | 491,000 | 646.82% | 6 | 60.00% |
| Enter lower limit for dollar amount: | ||||
| A | 4,000,000 | B | 900,000 | |
| Unit | Dollar | |||
| Item | Usage | Cost | Amount | Class |
| 1 | 2,500 | 360 | 900,000 | B |
| 2 | 1,000 | 70 | 70,000 | C |
| 3 | 2,400 | 500 | 1,200,000 | B |
| 4 | 1,500 | 100 | 150,000 | C |
| 5 | 700 | 70 | 49,000 | C |
| 6 | 1,000 | 1,000 | 1,000,000 | B |
| 7 | 200 | 210 | 42,000 | C |
| 8 | 1,000 | 4,000 | 4,000,000 | A |
| 9 | 8,000 | 10 | 80,000 | C |
| 10 | 500 | 200 | 100,000 | C |
A Dollar Amount Number of Items 0.52693979712817807 0.1 B Dollar Amount Number of Items 40.837834277433807 0.3 C Dollar Amount Number of Items 6.4681860097483863 0.6
EOQ
| Basic Economic Order Quantity (EOQ) Model | Basic | x | Carry | Order | Total | Q | |||||||||||||||||||
| <Back | 1 | 8 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||||
| Annual Demand | D = | 9600 | 30 | 240 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Ordering cost per order | S = | 75 | 60 | 480 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Annual carrying cost per unit | H = | 16 | 90 | 720 | 8000 | 8720 | |||||||||||||||||||
| Working days per year | D/Y = | 288 | 120 | 960 | 6000 | 6960 | |||||||||||||||||||
| Economic Order Quantity | EOQ = | 300 | 150 | 1200 | 4800 | 6000 | |||||||||||||||||||
| 180 | 1440 | 4000 | 5440 | ||||||||||||||||||||||
| Actual Order Quantity | Q = | 300 | 210 | 1680 | 3428.5714285714 | 5108.5714285714 | |||||||||||||||||||
| Increment | DQ = | 10 | 240 | 1920 | 3000 | 4920 | |||||||||||||||||||
| Number of orders per year | D/Q = | 32 | 270 | 2160 | 2666.6666666667 | 4826.6666666667 | |||||||||||||||||||
| Length of order cycle (days) | Q/D = | 9 | 300 | 2400 | 2400 | 4800 | |||||||||||||||||||
| Average Inventory | Q/2 = | 150 | 330 | 2640 | 2181.8181818182 | 4821.8181818182 | |||||||||||||||||||
| Annual carrying cost | (Q/2) * H = | 2400 | 360 | 2880 | 2000 | 4880 | |||||||||||||||||||
| Annual ordering cost | (D/Q) * S = | 2400 | 390 | 3120 | 1846.1538461539 | 4966.1538461539 | |||||||||||||||||||
| Total Annual Cost | TC = | 4800 | 420 | 3360 | 1714.2857142857 | 5074.2857142857 | |||||||||||||||||||
| 450 | 3600 | 1600 | 5200 | ||||||||||||||||||||||
| 480 | 3840 | 1500 | 5340 | ||||||||||||||||||||||
| 510 | 4080 | 1411.7647058823 | 5491.7647058824 | ||||||||||||||||||||||
| 540 | 4320 | 1333.3333333333 | 5653.3333333333 | ||||||||||||||||||||||
| 570 | 4560 | 1263.1578947368 | 5823.1578947368 | ||||||||||||||||||||||
| 600 | 4800 | 1200 | 6000 | ||||||||||||||||||||||
| 300 | 4800 | ||||||||||||||||||||||||
| 300 | 0 | ||||||||||||||||||||||||
| Start: | 0 | Stop: | 600 | ||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 9600 | ||||||||||||||||||||||
| Steps: | 20 | Step: | 30 | ||||||||||||||||||||||
| Basic Template: | You can simply copy the basic template below and paste into another worksheet. | ||||||||||||||||||||||||
| ^Top | |||||||||||||||||||||||||
| Basic Economic Order Quantity (EOQ) Model | |||||||||||||||||||||||||
| Annual Demand | D = | 9600 | |||||||||||||||||||||||
| Ordering cost per order | S = | 75 | |||||||||||||||||||||||
| Annual carrying cost per unit | H = | 16 | |||||||||||||||||||||||
| Working days per year | D/Y = | 360 | |||||||||||||||||||||||
| Economic Order Quantity | EOQ = | 300 | |||||||||||||||||||||||
| Actual Order Quantity | Q = | 300 | |||||||||||||||||||||||
| Number of orders per year | D/Q = | 32 | |||||||||||||||||||||||
| Length of order cycle (days) | Q/D = | 11.25 | |||||||||||||||||||||||
| Average Inventory | Q/2 = | 150 | |||||||||||||||||||||||
| Annual carrying cost | (Q/2) * H = | 2400 | |||||||||||||||||||||||
| Annual ordering cost | (D/Q) * S = | 2400 | |||||||||||||||||||||||
| Total Annual Cost | TC = | 4800 | |||||||||||||||||||||||
1 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 300 300 4800 0
Order Quantity (Q)
EPQ
| Economic Production Quantity (EPQ) Model | Basic | x | Carrying | Setup | Total | Q | |||||||||||||||||||
| <Back | 1 | 0.375 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||||
| Annual Demand | D = | 48000 | 240 | 90 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Setup cost | S = | 45 | 480 | 180 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Annual carrying cost per unit | H = | 1 | 720 | 270 | 3000 | 3270 | |||||||||||||||||||
| Production rate | p = | 800 | 960 | 360 | 2250 | 2610 | |||||||||||||||||||
| Usage rate | u = | 200 | 1200 | 450 | 1800 | 2250 | |||||||||||||||||||
| Production days per year | D/Y = | 240 | 1440 | 540 | 1500 | 2040 | |||||||||||||||||||
| Economic Run Quantity | Qp = | 2400 | 1680 | 630 | 1285.7142857143 | 1915.7142857143 | |||||||||||||||||||
| 1920 | 720 | 1125 | 1845 | ||||||||||||||||||||||
| 2160 | 810 | 1000 | 1810 | ||||||||||||||||||||||
| Actual Run Quantity | Q = | 2400 | 2400 | 900 | 900 | 1800 | |||||||||||||||||||
| Increment | DQ = | 100 | 2640 | 990 | 818.1818181818 | 1808.1818181818 | |||||||||||||||||||
| Number of runs per year | D/Q = | 20 | 2880 | 1080 | 750 | 1830 | |||||||||||||||||||
| Cycle time | Q/u = | 12 | 3120 | 1170 | 692.3076923077 | 1862.3076923077 | |||||||||||||||||||
| Run time | Q/p = | 3 | 3360 | 1260 | 642.8571428571 | 1902.8571428571 | |||||||||||||||||||
| Average Inventory | Iave = | 900 | 3600 | 1350 | 600 | 1950 | |||||||||||||||||||
| Maximum Inventory | Imax = | 1800 | 3840 | 1440 | 562.5 | 2002.5 | |||||||||||||||||||
| Annual carrying cost | Iave * H = | 900 | 4080 | 1530 | 529.4117647059 | 2059.4117647059 | |||||||||||||||||||
| Annual setup cost | (D/Q) * S = | 900 | 4320 | 1620 | 500 | 2120 | |||||||||||||||||||
| Total Annual Cost | TC = | 1800 | 4560 | 1710 | 473.6842105263 | 2183.6842105263 | |||||||||||||||||||
| 4800 | 1800 | 450 | 2250 | ||||||||||||||||||||||
| 2400 | 1800 | ||||||||||||||||||||||||
| 2400 | 0 | ||||||||||||||||||||||||
| Start: | 0 | Stop: | 4800 | ||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 4200 | ||||||||||||||||||||||
| Steps: | 20 | Step: | 240 | ||||||||||||||||||||||
| Basic Template: | You can simply copy the basic template below and paste into another worksheet. | ||||||||||||||||||||||||
| ^Top | |||||||||||||||||||||||||
| Economic Production Quantity (EPQ) Model | |||||||||||||||||||||||||
| Annual Demand | D = | 48000 | |||||||||||||||||||||||
| Setup cost | S = | 45 | |||||||||||||||||||||||
| Annual carrying cost per unit | H = | 1 | |||||||||||||||||||||||
| Production rate | p = | 800 | |||||||||||||||||||||||
| Usage rate | u = | 200 | |||||||||||||||||||||||
| Production days per year | D/Y = | 240 | |||||||||||||||||||||||
| Economic Run Quantity | Qp = | 2400 | |||||||||||||||||||||||
| Actual Run Quantity | Q = | 2400 | |||||||||||||||||||||||
| Increment | DQ = | 100 | |||||||||||||||||||||||
| Number of runs per year | D/Q = | 20 | |||||||||||||||||||||||
| Cycle time | Q/u = | 12 | |||||||||||||||||||||||
| Run time | Q/p = | 3 | |||||||||||||||||||||||
| Average Inventory | Iave = | 900 | |||||||||||||||||||||||
| Maximum Inventory | Imax = | 1800 | |||||||||||||||||||||||
| Annual carrying cost | Iave * H = | 900 | |||||||||||||||||||||||
| Annual setup cost | (D/Q) * S = | 900 | |||||||||||||||||||||||
| Total Annual Cost | TC = | 1800 |
1 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 2880 3120 3360 3600 3840 4080 4320 4560 4800 2400 2400 1800 0
Run Quantity (Q)
Quantity Discounts
| Quantity Discounts | Basic | 1 | 2 | 3 | 4 | 5 | 6 | 7 | |||||||||||||||||||||||
| <Back | Notes | Price Level: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | x | 1 | 50 | 80 | 100 | 0 | 0 | 0 | ||||||||||||||
| Minimum quantity for price | Qmin = | 1 | 50 | 80 | 100 | 1 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1 | 26114 | 24482 | 23666 | 22850 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Price | P = | 20.00 | 18.00 | 17.00 | 16.00 | 5 | 18288.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 5 | 18288.4 | 16656.4 | 15840.4 | 15024.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Optimal Q (for each price) | Qopt = | 70 | 70 | 80 | 100 | 10 | 17319.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 10 | 17319.2 | 15687.2 | 14871.2 | 14055.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Number of orders per year | D/Qopt = | 11.6571428571 | 11.6571428571 | 10.2 | 8.16 | 15 | 17002.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 15 | 17002.8 | 15370.8 | 14554.8 | 13738.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Average Inventory | Qopt/2 = | 35 | 35 | 40 | 50 | 20 | 16849.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 20 | 16849.6 | 15217.6 | 14401.6 | 13585.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Annual carrying cost | (Qopt/2) * H = | 140 | 140 | 160 | 200 | 25 | 16761.68 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 25 | 16761.68 | 15129.68 | 14313.68 | 13497.68 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Annual ordering cost | (D/Qopt) * S = | 139.8857142857 | 139.8857142857 | 122.4 | 97.92 | 30 | 16706.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 30 | 16706.4 | 15074.4 | 14258.4 | 13442.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Annual purchase cost | P * D = | 16320 | 14688 | 13872 | 13056 | 35 | 16669.7714285714 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 35 | 16669.7714285714 | 15037.7714285714 | 14221.7714285714 | 13405.7714285714 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Total Annual Cost | TC = | 16599.8857142857 | 14967.8857142857 | 14154.4 | 13353.92 | 40 | 16644.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 40 | 16644.8 | 15012.8 | 14196.8 | 13380.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| 45 | 16627.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 45 | 16627.6 | 14995.6 | 14179.6 | 13363.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Annual Demand | D = | 816 | 50 | 16615.84 | 14983.84 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 50 | 16615.84 | 14983.84 | 14167.84 | 13351.84 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Ordering cost per order | S = | 12 | 55 | 16608.0363636364 | 14976.0363636364 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 55 | 16608.0363636364 | 14976.0363636364 | 14160.0363636364 | 13344.0363636364 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost per unit: | H (fixed) = | 4 | 60 | 16603.2 | 14971.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 60 | 16603.2 | 14971.2 | 14155.2 | 13339.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 1 | TRUE | H (% of price) = | 65 | 16600.6461538462 | 14968.6461538462 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 65 | 16600.6461538462 | 14968.6461538462 | 14152.6461538462 | 13336.6461538462 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Optimal Q (overall) | Qopt = | 100 | 70 | 16599.8857142857 | 14967.8857142857 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 70 | 16599.8857142857 | 14967.8857142857 | 14151.8857142857 | 13335.8857142857 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 75 | 16600.56 | 14968.56 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 75 | 16600.56 | 14968.56 | 14152.56 | 13336.56 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Actual Order Quantity | Q = | 100 | 80 | 16602.4 | 14970.4 | 14154.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 80 | 16602.4 | 14970.4 | 14154.4 | 13338.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Increment | DQ = | 10 | 85 | 16605.2 | 14973.2 | 14157.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 85 | 16605.2 | 14973.2 | 14157.2 | 13341.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Price | P = | 16 | 90 | 16608.8 | 14976.8 | 14160.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 90 | 16608.8 | 14976.8 | 14160.8 | 13344.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Number of orders per year | D/Q = | 8.16 | 95 | 16613.0736842105 | 14981.0736842105 | 14165.0736842105 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 95 | 16613.0736842105 | 14981.0736842105 | 14165.0736842105 | 13349.0736842105 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Average Inventory | Q/2 = | 50 | 100 | 16617.92 | 14985.92 | 14169.92 | 13353.92 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 100 | 16617.92 | 14985.92 | 14169.92 | 13353.92 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost | (Q/2) * H = | 200 | 105 | 16623.2571428571 | 14991.2571428571 | 14175.2571428571 | 13359.2571428571 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 105 | 16623.2571428571 | 14991.2571428571 | 14175.2571428571 | 13359.2571428571 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual ordering cost | (D/Q) * S = | 97.92 | 110 | 16629.0181818182 | 14997.0181818182 | 14181.0181818182 | 13365.0181818182 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 110 | 16629.0181818182 | 14997.0181818182 | 14181.0181818182 | 13365.0181818182 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual purchase cost | P * D = | 13056 | 115 | 16635.147826087 | 15003.147826087 | 14187.147826087 | 13371.147826087 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 115 | 16635.147826087 | 15003.147826087 | 14187.147826087 | 13371.147826087 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Total Annual Cost | TC = | 13353.92 | 120 | 16641.6 | 15009.6 | 14193.6 | 13377.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 120 | 16641.6 | 15009.6 | 14193.6 | 13377.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 125 | 16648.336 | 15016.336 | 14200.336 | 13384.336 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 125 | 16648.336 | 15016.336 | 14200.336 | 13384.336 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 130 | 16655.3230769231 | 15023.3230769231 | 14207.3230769231 | 13391.3230769231 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 130 | 16655.3230769231 | 15023.3230769231 | 14207.3230769231 | 13391.3230769231 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Notes: | Use radio buttons to select holding cost as a fixed amount or as percent of price. | 135 | 16662.5333333333 | 15030.5333333333 | 14214.5333333333 | 13398.5333333333 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 135 | 16662.5333333333 | 15030.5333333333 | 14214.5333333333 | 13398.5333333333 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||
| Enter holding cost as a fixed amount in cell E15 or as a percent of price in cell E16. | 140 | 16669.9428571429 | 15037.9428571429 | 14221.9428571429 | 13405.9428571429 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 140 | 16669.9428571429 | 15037.9428571429 | 14221.9428571429 | 13405.9428571429 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| ^Top | 145 | 16677.5310344828 | 15045.5310344828 | 14229.5310344828 | 13413.5310344828 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 145 | 16677.5310344828 | 15045.5310344828 | 14229.5310344828 | 13413.5310344828 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| 150 | 16685.28 | 15053.28 | 14237.28 | 13421.28 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 150 | 16685.28 | 15053.28 | 14237.28 | 13421.28 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 155 | 16693.1741935484 | 15061.1741935484 | 14245.1741935484 | 13429.1741935484 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 155 | 16693.1741935484 | 15061.1741935484 | 14245.1741935484 | 13429.1741935484 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 160 | 16701.2 | 15069.2 | 14253.2 | 13437.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 160 | 16701.2 | 15069.2 | 14253.2 | 13437.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 165 | 16709.3454545455 | 15077.3454545455 | 14261.3454545455 | 13445.3454545455 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 165 | 16709.3454545455 | 15077.3454545455 | 14261.3454545455 | 13445.3454545455 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 170 | 16717.6 | 15085.6 | 14269.6 | 13453.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 170 | 16717.6 | 15085.6 | 14269.6 | 13453.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 175 | 16725.9542857143 | 15093.9542857143 | 14277.9542857143 | 13461.9542857143 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 175 | 16725.9542857143 | 15093.9542857143 | 14277.9542857143 | 13461.9542857143 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 180 | 16734.4 | 15102.4 | 14286.4 | 13470.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 180 | 16734.4 | 15102.4 | 14286.4 | 13470.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 185 | 16742.9297297297 | 15110.9297297297 | 14294.9297297297 | 13478.9297297297 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 185 | 16742.9297297297 | 15110.9297297297 | 14294.9297297297 | 13478.9297297297 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 190 | 16751.5368421053 | 15119.5368421053 | 14303.5368421053 | 13487.5368421053 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 190 | 16751.5368421053 | 15119.5368421053 | 14303.5368421053 | 13487.5368421053 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 195 | 16760.2153846154 | 15128.2153846154 | 14312.2153846154 | 13496.2153846154 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 195 | 16760.2153846154 | 15128.2153846154 | 14312.2153846154 | 13496.2153846154 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 200 | 16768.96 | 15136.96 | 14320.96 | 13504.96 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 200 | 16768.96 | 15136.96 | 14320.96 | 13504.96 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 100 | 0 | 100 | 16617.92 | 14985.92 | 14169.92 | 13353.92 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||||||||
| 100 | 13353.92 | 100 | 16617.92 | 14888.5892434192 | 14072.657684878 | 13256.6958173942 | |||||||||||||||||||||||||
| Basic Template: | You can simply copy the basic template below and paste into another worksheet. | Start: | 0 | Stop: | 200 | ||||||||||||||||||||||||||
| ^Top | Min Y : | 0 | Max Y: | 24899.8285714286 | |||||||||||||||||||||||||||
| Steps: | 40 | Step: | 5 | ||||||||||||||||||||||||||||
| Quantity Discounts | |||||||||||||||||||||||||||||||
| Price Level: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | ||||||||||||||||||||||||
| Minimum quantity for price | Qmin = | 1 | 50 | 80 | 100 | ||||||||||||||||||||||||||
| Price | P = | 20.00 | 18.00 | 17.00 | 16.00 | ||||||||||||||||||||||||||
| Optimal Q (for each price) | Qopt = | 70 | 70 | 80 | 100 | ||||||||||||||||||||||||||
| Number of orders per year | D/Qopt = | 11.6571428571 | 11.6571428571 | 10.2 | 8.16 | ||||||||||||||||||||||||||
| Average Inventory | Qopt/2 = | 35 | 35 | 40 | 50 | ||||||||||||||||||||||||||
| Annual carrying cost | (Qopt/2) * H = | 140 | 140 | 160 | 200 | ||||||||||||||||||||||||||
| Annual ordering cost | (D/Qopt) * S = | 139.8857142857 | 139.8857142857 | 122.4 | 97.92 | ||||||||||||||||||||||||||
| Annual purchase cost | P * D = | 16320 | 14688 | 13872 | 13056 | ||||||||||||||||||||||||||
| Total Annual Cost | TC = | 16599.8857142857 | 14967.8857142857 | 14154.4 | 13353.92 | ||||||||||||||||||||||||||
| Annual Demand | D = | 816 | |||||||||||||||||||||||||||||
| Ordering cost per order | S = | 12 | |||||||||||||||||||||||||||||
| Annual carrying cost per unit: | H (fixed) = | 4 | <Must be blank if holding cost is a percent of price | ||||||||||||||||||||||||||||
| H (% of price) = | |||||||||||||||||||||||||||||||
1 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 100 100 0 13353.92
Order Quantity (Q)
Fixed
Percent of Price
ROP
| Reorder Point (ROP) with EOQ Ordering | Basic | |||||||||||||
| <Back | 14 | ERROR:#NUM! | ||||||||||||
| 14 | ERROR:#NUM! | |||||||||||||
| Average demand | d = | 2 | 14 | ERROR:#NUM! | ||||||||||
| Std dev demand | sd = | 0 | 14 | ERROR:#NUM! | ||||||||||
| Average lead time | LT = | 7 | 14 | ERROR:#NUM! | ||||||||||
| Std dev lead time | sLT = | 0 | 14 | ERROR:#NUM! | ||||||||||
| Service level | SL = | 0.4 | 14 | ERROR:#NUM! | ||||||||||
| Increment | DSL = | 0.05 | 14 | ERROR:#NUM! | ||||||||||
| Stock out risk | 0.6 | 14 | ERROR:#NUM! | |||||||||||
| Average demand during lead time | dLT = | 14 | 14 | ERROR:#N/A | 14 | ERROR:#NUM! | ||||||||
| Std dev demand during lead time | sdLT = | 0 | 14 | 14 | 14 | ERROR:#NUM! | ||||||||
| z = | -0.2533471031 | 14 | ERROR:#N/A | 14 | 0 | |||||||||
| Safety stock | SS = | 0 | 14 | 1 | ||||||||||
| Reorder point | ROP = | 14 | 14 | 0 | ||||||||||
| 14 | 1 | |||||||||||||
| Basic Template: | You can simply copy the basic template below and paste into another worksheet. | |||||||||||||
| ^Top | ||||||||||||||
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| Average demand | d = | 2 | ||||||||||||
| Std dev demand | sd = | 0 | ||||||||||||
| Average lead time | LT = | 7 | ||||||||||||
| Std dev lead time | sLT = | 0 | ||||||||||||
| Service level | SL = | 0.4 | ||||||||||||
| Stock out risk | 0.6 | |||||||||||||
| Average demand during lead time | dLT = | 14 | ||||||||||||
| Std dev demand during lead time | sdLT = | 0 | ||||||||||||
| z = | -0.2533471031 | |||||||||||||
| Safety stock | SS = | 0 | ||||||||||||
| Reorder point | ROP = | 14 |
Fixed Order Interval
| Fixed Order Interval Model | Basic | |||||||||
| <Back | ||||||||||
| Average demand | d = | 30 | ||||||||
| Std dev demand | sd = | 3 | ||||||||
| Lead time | LT = | 2 | ||||||||
| Amount on hand at reorder time | A = | 71 | ||||||||
| Order interval | OI = | 7 | ||||||||
| Service level | SL = | 0.99 | ||||||||
| Increment | DSL = | 0.01 | ||||||||
| Stock out risk | 0.01 | 199 | 270 | ERROR:#N/A | ERROR:#N/A | |||||
| Average demand during lead time | dLT = | 270 | 199 | 270 | 219.9371308664 | ERROR:#N/A | ||||
| Safety stock | SS = | 20.9371308664 | 199 | 270 | ERROR:#N/A | ERROR:#N/A | ||||
| Amount to order | 219.9371308664 | |||||||||
| Basic Template: | You can simply copy the basic template below and paste into another worksheet. | |||||||||
| ^Top | ||||||||||
| Fixed Order Interval Model | ||||||||||
| Average demand | d = | 30 | ||||||||
| Std dev demand | sd = | 3 | ||||||||
| Lead time | LT = | 2 | ||||||||
| Amount on hand at reorder time | A = | 71 | ||||||||
| Order interval | OI = | 7 | ||||||||
| Service level | SL = | 0.99 | ||||||||
| Stock out risk | 0.01 | |||||||||
| Average demand during lead time | dLT = | 270 | ||||||||
| Safety stock | SS = | 20.9371308664 | ||||||||
| Amount to order | 219.9371308664 |
Single Period
| Single Period Model | Basic | |||||||||
| <Back | ||||||||||
| Select demand distribution: | Uniform | |||||||||
| 1 | ||||||||||
| Shortage cost (revenue - cost) | Cs = | 0.6 | 0.4 | |||||||
| Excess cost (cost - salvage) | Ce = | 0.2 | ||||||||
| Minimum demand | 300 | |||||||||
| Maximum demand | 500 | |||||||||
| Optimal Service Level | SLo = | 0.75 | ||||||||
| Optimal Stocking Level | So = | 450 | ||||||||
| Actual Stocking Level | S = | 450 | ||||||||
| Increment | DS = | 10 | ||||||||
| Actual Service Level | SL = | 0.7500 | ||||||||
| Balance: | ||||||||||
| Ce * Service Level | 0.15 | |||||||||
| Cs * (1 - Service Level) | 0.15 | |||||||||
| Discrete Distribution: | Demand | Freq | Cum | |||||||
| Basic Template: | You can simply copy the basic template below and paste into another worksheet. | |||||||||
| ^Top | ||||||||||
| Single Period Model | Demand distribution: | Uniform | Single Period Model | Demand distribution: | Normal | |||||
| Shortage cost (revenue - cost) | Cs = | 0.6 | Shortage cost (revenue - cost) | Cs = | 0.6 | |||||
| Excess cost (cost - salvage) | Ce = | 0.2 | Excess cost (cost - salvage) | Ce = | 0.2 | |||||
| Minimum demand | 300 | Average demand | 200 | |||||||
| Maximum demand | 500 | Std dev demand | 10 | |||||||
| Optimal Service Level | SLo = | 0.75 | Optimal Service Level | SLo = | 0.75 | |||||
| Optimal Stocking Level | So = | 450 | Optimal Stocking Level | So = | 206.744897502 | |||||
| Actual Stocking Level | S = | 450 | Actual Stocking Level | S = | 207 | |||||
| Actual Service Level | SL = | 0.7500 | Actual Service Level | SL = | 0.7580 | |||||
| Balance: | Balance: | |||||||||
| Ce * Service Level | 0.15 | Ce * Service Level | 0.1516072696 | |||||||
| Cs * (1 - Service Level) | 0.15 | Cs * (1 - Service Level) | 0.1451781913 | |||||||
| Single Period Model | Demand distribution: | Poisson | Single Period Model | Demand distribution: | Discrete | |||||
| Shortage cost (revenue - cost) | Cs = | 3 | Shortage cost (revenue - cost) | Cs = | 1.6 | |||||
| Excess cost (cost - salvage) | Ce = | 2 | Excess cost (cost - salvage) | Ce = | 0.8 | |||||
| Average demand | 4 | |||||||||
| Optimal Service Level | SLo = | 0.6 | Optimal Service Level | SLo = | 0.6666666667 | |||||
| Adjust S until SL >= SLo | Adjust S until SL >= SLo | |||||||||
| Actual Stocking Level | S = | 4 | Actual Stocking Level | S = | 25 | |||||
| Actual Service Level | SL = | 0.6288 | Actual Service Level | SL = | 0.7300 | |||||
| Balance: | Balance: | |||||||||
| Ce * Service Level | 1.2576738704 | Ce * Service Level | 0.584 | |||||||
| Cs * (1 - Service Level) | 1.1134891945 | Cs * (1 - Service Level) | 0.432 | |||||||
| Discrete Distribution: | ||||||||||
| Demand | Freq | Cum | ||||||||
| 19 | 0.01 | 0.01 | ||||||||
| 20 | 0.05 | 0.06 | ||||||||
| 21 | 0.12 | 0.18 | ||||||||
| 22 | 0.18 | 0.36 | ||||||||
| 23 | 0.13 | 0.49 | ||||||||
| 24 | 0.14 | 0.63 | ||||||||
| 25 | 0.1 | 0.73 | ||||||||
| 26 | 0.11 | 0.84 | ||||||||
| 27 | 0.1 | 0.94 | ||||||||
| 28 | 0.04 | 0.98 | ||||||||
| 29 | 0.02 | 1 | ||||||||
| 1 |
Uniform
Normal
Poisson
Discrete
Lecture
| Lecture Suggestions - Chapter 12 | |
| <Back | |
| Example 1: ABC Classification System | |
| 1. | Select the Example 1 worksheet |
| 2. | You may delete and re-enter the usage and unit cost data for the 12 items if you want. Note that |
| although the 12 items for his example are in order according to dollar value, this is not necessary, | |
| the items can be entered in any order. | |
| 3. | Delete the values for A and B. |
| 4. | Initialize A and B by clicking the spinner button for A up two times and the spinner button for B |
| up one time, you should have A = 42,000 and B=18,000. | |
| 5. | Scroll down so you can observe all 12 items in the table as you change the values of A and B. |
| A and B are the lower limits for the A and B classifications and as you click a spinner button the | |
| value for A or B will change to the next higher (or lower) dollar value in the table. At the same time | |
| all the items are classified according to the current values for A and B. | |
| 6. | Now scroll back up so you can watch the graph and the table at the top of the template and |
| adjust the values of A and B to get the desired characteristics for each class, i.e. high value, | |
| low volume in classification A and low value, high volume in classification C. | |
| Example 18: Single Period Model | |
| 1. | Select the Example 18 worksheet |
| 2. | Select Poisson for the demand distribution. |
| 3. | Enter data: Cs = 3, Ce = 2, and average demand = 4 (all given). |
| 4. | Note that optimal service level = .60. |
| 5. | Set actual stocking level = 0 and note that the service level is computed (according to the |
| Poisson distribution) to be .0183, i.e. 18% of the time there will be a demand of zero. | |
| 6. | Increment the actual stocking level to 1 and note that the probability of demand <= 1 is .0916. |
| 7. | Point out in the graph that the blue bar (expected shortage cost) is high when the actual stocking |
| level is low and decreases with increasing actual stocking level (because the probability of a | |
| shortage goes down). The optimal actual stocking level will occur when the blue and red | |
| bars are balanced, i.e. you balance the expected shortage cost with the expected excess cost. | |
| 7. | Finally, solve for the optimal actual stocking level - increase the actual stocking level until the |
| resulting service level just exceeds .60 - and at the same time red and blue bars in the graph | |
| will come the closest to balancing. This will happen at actual stocking level = 4. |
Example 1
| ABC Classification System | ||||
| <Back | ||||
| Dollar Amount | Number of Items | |||
| Class | Total | Percent | Total | Percent |
| A | 40,000 | 52.69% | 1 | 10.00% |
| B | 31,000 | 40.84% | 3 | 30.00% |
| C | 4,910 | 6.47% | 6 | 60.00% |
| Enter lower limit for dollar amount: | ||||
| A | 40,000 | B | 9,000 | |
| Unit | Dollar | |||
| Item | Usage | Cost | Amount | Class |
| 1 | 25 | 360 | 9,000 | B |
| 2 | 10 | 70 | 700 | C |
| 3 | 24 | 500 | 12,000 | B |
| 4 | 15 | 100 | 1,500 | C |
| 5 | 7 | 70 | 490 | C |
| 6 | 10 | 1,000 | 10,000 | B |
| 7 | 2 | 210 | 420 | C |
| 8 | 10 | 4,000 | 40,000 | A |
| 9 | 80 | 10 | 800 | C |
| 10 | 5 | 200 | 1,000 | C |
Example 2
| Basic Economic Order Quantity (EOQ) Model | x | Carry | Order | Total | Q | ||||||||||||||||||||
| <Back | 1 | 8 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||||
| Annual Demand | D = | 9600 | 30 | 240 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Ordering cost per order | S = | 75 | 60 | 480 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Annual carrying cost per unit | H = | 16 | 90 | 720 | 8000 | 8720 | |||||||||||||||||||
| Working days per year | D/Y = | 288 | 120 | 960 | 6000 | 6960 | |||||||||||||||||||
| Economic Order Quantity | EOQ = | 300 | 150 | 1200 | 4800 | 6000 | |||||||||||||||||||
| 180 | 1440 | 4000 | 5440 | ||||||||||||||||||||||
| Actual Order Quantity | Q = | 300 | 210 | 1680 | 3428.5714285714 | 5108.5714285714 | |||||||||||||||||||
| Increment | DQ = | 10 | 240 | 1920 | 3000 | 4920 | |||||||||||||||||||
| Number of orders per year | D/Q = | 32 | 270 | 2160 | 2666.6666666667 | 4826.6666666667 | |||||||||||||||||||
| Length of order cycle (days) | Q/D = | 9 | 300 | 2400 | 2400 | 4800 | |||||||||||||||||||
| Average Inventory | Q/2 = | 150 | 330 | 2640 | 2181.8181818182 | 4821.8181818182 | |||||||||||||||||||
| Annual carrying cost | (Q/2) * H = | 2400 | 360 | 2880 | 2000 | 4880 | |||||||||||||||||||
| Annual ordering cost | (D/Q) * S = | 2400 | 390 | 3120 | 1846.1538461539 | 4966.1538461539 | |||||||||||||||||||
| Total Annual Cost | TC = | 4800 | 420 | 3360 | 1714.2857142857 | 5074.2857142857 | |||||||||||||||||||
| 450 | 3600 | 1600 | 5200 | ||||||||||||||||||||||
| 480 | 3840 | 1500 | 5340 | ||||||||||||||||||||||
| 510 | 4080 | 1411.7647058823 | 5491.7647058824 | ||||||||||||||||||||||
| 540 | 4320 | 1333.3333333333 | 5653.3333333333 | ||||||||||||||||||||||
| 570 | 4560 | 1263.1578947368 | 5823.1578947368 | ||||||||||||||||||||||
| 600 | 4800 | 1200 | 6000 | ||||||||||||||||||||||
| 300 | 4800 | ||||||||||||||||||||||||
| 300 | 0 | ||||||||||||||||||||||||
| Start: | 0 | Stop: | 600 | ||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 9600 | ||||||||||||||||||||||
| Steps: | 20 | Step: | 30 |
1 30 60 90 120 150 180 210 240 270 300 330 360 390 420 450 480 510 540 570 600 300 300 4800 0
Order Quantity (Q)
Example 3
| Basic Economic Order Quantity (EOQ) Model | x | Carry | Order | Total | Q | ||||||||||||||||||||
| <Back | 1 | 18 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||||
| Annual Demand | D = | 3600 | 10 | 180 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Ordering cost per order | S = | 50 | 20 | 360 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Annual carrying cost per unit | H = | 36 | 30 | 540 | 6000 | 6540 | |||||||||||||||||||
| Working days per year | D/Y = | 360 | 40 | 720 | 4500 | 5220 | |||||||||||||||||||
| Economic Order Quantity | EOQ = | 100 | 50 | 900 | 3600 | 4500 | |||||||||||||||||||
| 60 | 1080 | 3000 | 4080 | ||||||||||||||||||||||
| Actual Order Quantity | Q = | 100 | 70 | 1260 | 2571.4285714286 | 3831.4285714286 | |||||||||||||||||||
| Increment | DQ = | 1 | 80 | 1440 | 2250 | 3690 | |||||||||||||||||||
| Number of orders per year | D/Q = | 36 | 90 | 1620 | 2000 | 3620 | |||||||||||||||||||
| Length of order cycle (days) | Q/D = | 10 | 100 | 1800 | 1800 | 3600 | |||||||||||||||||||
| Average Inventory | Q/2 = | 50 | 110 | 1980 | 1636.3636363636 | 3616.3636363636 | |||||||||||||||||||
| Annual carrying cost | (Q/2) * H = | 1800 | 120 | 2160 | 1500 | 3660 | |||||||||||||||||||
| Annual ordering cost | (D/Q) * S = | 1800 | 130 | 2340 | 1384.6153846154 | 3724.6153846154 | |||||||||||||||||||
| Total Annual Cost | TC = | 3600 | 140 | 2520 | 1285.7142857143 | 3805.7142857143 | |||||||||||||||||||
| 150 | 2700 | 1200 | 3900 | ||||||||||||||||||||||
| 160 | 2880 | 1125 | 4005 | ||||||||||||||||||||||
| 170 | 3060 | 1058.8235294118 | 4118.8235294118 | ||||||||||||||||||||||
| 180 | 3240 | 1000 | 4240 | ||||||||||||||||||||||
| 190 | 3420 | 947.3684210526 | 4367.3684210526 | ||||||||||||||||||||||
| 200 | 3600 | 900 | 4500 | ||||||||||||||||||||||
| 100 | 3600 | ||||||||||||||||||||||||
| 100 | 0 | ||||||||||||||||||||||||
| Start: | 0 | Stop: | 200 | ||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 7200 | ||||||||||||||||||||||
| Steps: | 20 | Step: | 10 |
1 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 190 200 100 100 3600 0
Order Quantity (Q)
Example 4
| Economic Production Quantity (EPQ) Model | x | Carrying | Setup | Total | Q | ||||||||||||||||||||
| <Back | 1 | 0.375 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||||
| Annual Demand | D = | 48000 | 240 | 90 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Setup cost | S = | 45 | 480 | 180 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Annual carrying cost per unit | H = | 1 | 720 | 270 | 3000 | 3270 | |||||||||||||||||||
| Production rate | p = | 800 | 960 | 360 | 2250 | 2610 | |||||||||||||||||||
| Usage rate | u = | 200 | 1200 | 450 | 1800 | 2250 | |||||||||||||||||||
| Production days per year | D/Y = | 240 | 1440 | 540 | 1500 | 2040 | |||||||||||||||||||
| Economic Run Quantity | Qp = | 2400 | 1680 | 630 | 1285.7142857143 | 1915.7142857143 | |||||||||||||||||||
| 1920 | 720 | 1125 | 1845 | ||||||||||||||||||||||
| 2160 | 810 | 1000 | 1810 | ||||||||||||||||||||||
| Actual Run Quantity | Q = | 2400 | 2400 | 900 | 900 | 1800 | |||||||||||||||||||
| Increment | DQ = | 100 | 2640 | 990 | 818.1818181818 | 1808.1818181818 | |||||||||||||||||||
| Number of runs per year | D/Q = | 20 | 2880 | 1080 | 750 | 1830 | |||||||||||||||||||
| Cycle time | Q/u = | 12 | 3120 | 1170 | 692.3076923077 | 1862.3076923077 | |||||||||||||||||||
| Run time | Q/p = | 3 | 3360 | 1260 | 642.8571428571 | 1902.8571428571 | |||||||||||||||||||
| Average Inventory | Iave = | 900 | 3600 | 1350 | 600 | 1950 | |||||||||||||||||||
| Maximum Inventory | Imax = | 1800 | 3840 | 1440 | 562.5 | 2002.5 | |||||||||||||||||||
| Annual carrying cost | Iave * H = | 900 | 4080 | 1530 | 529.4117647059 | 2059.4117647059 | |||||||||||||||||||
| Annual setup cost | (D/Q) * S = | 900 | 4320 | 1620 | 500 | 2120 | |||||||||||||||||||
| Total Annual Cost | TC = | 1800 | 4560 | 1710 | 473.6842105263 | 2183.6842105263 | |||||||||||||||||||
| 4800 | 1800 | 450 | 2250 | ||||||||||||||||||||||
| 2400 | 1800 | ||||||||||||||||||||||||
| 2400 | 0 | ||||||||||||||||||||||||
| Start: | 0 | Stop: | 4800 | ||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 4200 | ||||||||||||||||||||||
| Steps: | 20 | Step: | 240 |
1 240 480 720 960 1200 1440 1680 1920 2160 2400 2640 2880 3120 3360 3600 3840 4080 4320 4560 4800 2400 2400 1800 0
Run Quantity (Q)
Example 5
| Quantity Discounts | 1 | 2 | 3 | 4 | 5 | 6 | 7 | ||||||||||||||||||||||||
| <Back | Notes | Price Level: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | x | 1 | 50 | 80 | 100 | 0 | 0 | 0 | ||||||||||||||
| Minimum quantity for price | Qmin = | 1 | 50 | 80 | 100 | 1 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1 | 26114 | 24482 | 23666 | 22850 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Price | P = | 20.00 | 18.00 | 17.00 | 16.00 | 5 | 18288.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 5 | 18288.4 | 16656.4 | 15840.4 | 15024.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Optimal Q (for each price) | Qopt = | 70 | 70 | 80 | 100 | 10 | 17319.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 10 | 17319.2 | 15687.2 | 14871.2 | 14055.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Number of orders per year | D/Qopt = | 11.6571428571 | 11.6571428571 | 10.2 | 8.16 | 15 | 17002.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 15 | 17002.8 | 15370.8 | 14554.8 | 13738.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Average Inventory | Qopt/2 = | 35 | 35 | 40 | 50 | 20 | 16849.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 20 | 16849.6 | 15217.6 | 14401.6 | 13585.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Annual carrying cost | (Qopt/2) * H = | 140 | 140 | 160 | 200 | 25 | 16761.68 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 25 | 16761.68 | 15129.68 | 14313.68 | 13497.68 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Annual ordering cost | (D/Qopt) * S = | 139.8857142857 | 139.8857142857 | 122.4 | 97.92 | 30 | 16706.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 30 | 16706.4 | 15074.4 | 14258.4 | 13442.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Annual purchase cost | P * D = | 16320 | 14688 | 13872 | 13056 | 35 | 16669.7714285714 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 35 | 16669.7714285714 | 15037.7714285714 | 14221.7714285714 | 13405.7714285714 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| Total Annual Cost | TC = | 16599.8857142857 | 14967.8857142857 | 14154.4 | 13353.92 | 40 | 16644.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 40 | 16644.8 | 15012.8 | 14196.8 | 13380.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||
| 45 | 16627.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 45 | 16627.6 | 14995.6 | 14179.6 | 13363.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Annual Demand | D = | 816 | 50 | 16615.84 | 14983.84 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 50 | 16615.84 | 14983.84 | 14167.84 | 13351.84 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Ordering cost per order | S = | 12 | 55 | 16608.0363636364 | 14976.0363636364 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 55 | 16608.0363636364 | 14976.0363636364 | 14160.0363636364 | 13344.0363636364 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost per unit: | H (fixed) = | 4 | 60 | 16603.2 | 14971.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 60 | 16603.2 | 14971.2 | 14155.2 | 13339.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 1 | TRUE | H (% of price) = | 65 | 16600.6461538462 | 14968.6461538462 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 65 | 16600.6461538462 | 14968.6461538462 | 14152.6461538462 | 13336.6461538462 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Optimal Q (overall) | Qopt = | 100 | 70 | 16599.8857142857 | 14967.8857142857 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 70 | 16599.8857142857 | 14967.8857142857 | 14151.8857142857 | 13335.8857142857 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 75 | 16600.56 | 14968.56 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 75 | 16600.56 | 14968.56 | 14152.56 | 13336.56 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Actual Order Quantity | Q = | 100 | 80 | 16602.4 | 14970.4 | 14154.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 80 | 16602.4 | 14970.4 | 14154.4 | 13338.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Increment | DQ = | 10 | 85 | 16605.2 | 14973.2 | 14157.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 85 | 16605.2 | 14973.2 | 14157.2 | 13341.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Price | P = | 16 | 90 | 16608.8 | 14976.8 | 14160.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 90 | 16608.8 | 14976.8 | 14160.8 | 13344.8 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Number of orders per year | D/Q = | 8.16 | 95 | 16613.0736842105 | 14981.0736842105 | 14165.0736842105 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 95 | 16613.0736842105 | 14981.0736842105 | 14165.0736842105 | 13349.0736842105 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Average Inventory | Q/2 = | 50 | 100 | 16617.92 | 14985.92 | 14169.92 | 13353.92 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 100 | 16617.92 | 14985.92 | 14169.92 | 13353.92 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost | (Q/2) * H = | 200 | 105 | 16623.2571428571 | 14991.2571428571 | 14175.2571428571 | 13359.2571428571 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 105 | 16623.2571428571 | 14991.2571428571 | 14175.2571428571 | 13359.2571428571 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual ordering cost | (D/Q) * S = | 97.92 | 110 | 16629.0181818182 | 14997.0181818182 | 14181.0181818182 | 13365.0181818182 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 110 | 16629.0181818182 | 14997.0181818182 | 14181.0181818182 | 13365.0181818182 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual purchase cost | P * D = | 13056 | 115 | 16635.147826087 | 15003.147826087 | 14187.147826087 | 13371.147826087 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 115 | 16635.147826087 | 15003.147826087 | 14187.147826087 | 13371.147826087 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Total Annual Cost | TC = | 13353.92 | 120 | 16641.6 | 15009.6 | 14193.6 | 13377.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 120 | 16641.6 | 15009.6 | 14193.6 | 13377.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 125 | 16648.336 | 15016.336 | 14200.336 | 13384.336 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 125 | 16648.336 | 15016.336 | 14200.336 | 13384.336 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 130 | 16655.3230769231 | 15023.3230769231 | 14207.3230769231 | 13391.3230769231 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 130 | 16655.3230769231 | 15023.3230769231 | 14207.3230769231 | 13391.3230769231 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Notes: | Use radio buttons to select holding cost as a fixed amount or as percent of price. | 135 | 16662.5333333333 | 15030.5333333333 | 14214.5333333333 | 13398.5333333333 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 135 | 16662.5333333333 | 15030.5333333333 | 14214.5333333333 | 13398.5333333333 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||
| Enter holding cost as a fixed amount in cell E15 or as a percent of price in cell E16. | 140 | 16669.9428571429 | 15037.9428571429 | 14221.9428571429 | 13405.9428571429 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 140 | 16669.9428571429 | 15037.9428571429 | 14221.9428571429 | 13405.9428571429 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| ^Top | 145 | 16677.5310344828 | 15045.5310344828 | 14229.5310344828 | 13413.5310344828 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 145 | 16677.5310344828 | 15045.5310344828 | 14229.5310344828 | 13413.5310344828 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| 150 | 16685.28 | 15053.28 | 14237.28 | 13421.28 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 150 | 16685.28 | 15053.28 | 14237.28 | 13421.28 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 155 | 16693.1741935484 | 15061.1741935484 | 14245.1741935484 | 13429.1741935484 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 155 | 16693.1741935484 | 15061.1741935484 | 14245.1741935484 | 13429.1741935484 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 160 | 16701.2 | 15069.2 | 14253.2 | 13437.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 160 | 16701.2 | 15069.2 | 14253.2 | 13437.2 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 165 | 16709.3454545455 | 15077.3454545455 | 14261.3454545455 | 13445.3454545455 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 165 | 16709.3454545455 | 15077.3454545455 | 14261.3454545455 | 13445.3454545455 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 170 | 16717.6 | 15085.6 | 14269.6 | 13453.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 170 | 16717.6 | 15085.6 | 14269.6 | 13453.6 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 175 | 16725.9542857143 | 15093.9542857143 | 14277.9542857143 | 13461.9542857143 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 175 | 16725.9542857143 | 15093.9542857143 | 14277.9542857143 | 13461.9542857143 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 180 | 16734.4 | 15102.4 | 14286.4 | 13470.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 180 | 16734.4 | 15102.4 | 14286.4 | 13470.4 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 185 | 16742.9297297297 | 15110.9297297297 | 14294.9297297297 | 13478.9297297297 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 185 | 16742.9297297297 | 15110.9297297297 | 14294.9297297297 | 13478.9297297297 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 190 | 16751.5368421053 | 15119.5368421053 | 14303.5368421053 | 13487.5368421053 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 190 | 16751.5368421053 | 15119.5368421053 | 14303.5368421053 | 13487.5368421053 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 195 | 16760.2153846154 | 15128.2153846154 | 14312.2153846154 | 13496.2153846154 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 195 | 16760.2153846154 | 15128.2153846154 | 14312.2153846154 | 13496.2153846154 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 200 | 16768.96 | 15136.96 | 14320.96 | 13504.96 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 200 | 16768.96 | 15136.96 | 14320.96 | 13504.96 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 100 | 0 | 100 | 16617.92 | 14985.92 | 14169.92 | 13353.92 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||||||||
| 100 | 13353.92 | 100 | 16617.92 | 14888.5892434192 | 14072.657684878 | 13256.6958173942 | |||||||||||||||||||||||||
| Start: | 0 | Stop: | 200 | ||||||||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 24899.8285714286 | ||||||||||||||||||||||||||||
| Steps: | 40 | Step: | 5 | ||||||||||||||||||||||||||||
1 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180 185 190 195 200 100 100 0 13353.92
Order Quantity (Q)
Fixed
Percent of Price
Example 6
| Quantity Discounts | 1 | 2 | 3 | 4 | 5 | 6 | 7 | ||||||||||||||||||||||||
| <Back | Notes | Price Level: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | x | 1 | 500 | 1000 | 0 | 0 | 0 | 0 | ||||||||||||||
| Minimum quantity for price | Qmin = | 1 | 500 | 1000 | 1 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1 | 123600.18 | 123400.17 | 123200.16 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Price | P = | 0.90 | 0.85 | 0.80 | 50 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 50 | 6009 | 5808.5 | 5608 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Optimal Q (for each price) | Qopt = | 816 | 840 | 1000 | 100 | 4818 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 100 | 4818 | 4617 | 4416 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Number of orders per year | D/Qopt = | 4.9019607843 | 4.7619047619 | 4 | 150 | 4427 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 150 | 4427 | 4225.5 | 4024 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Average Inventory | Qopt/2 = | 408 | 420 | 500 | 200 | 4236 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 200 | 4236 | 4034 | 3832 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Annual carrying cost | (Qopt/2) * H = | 146.88 | 142.8 | 160 | 250 | 4125 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 250 | 4125 | 3922.5 | 3720 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Annual ordering cost | (D/Qopt) * S = | 147.0588235294 | 142.8571428571 | 120 | 300 | 4054 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 300 | 4054 | 3851 | 3648 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Annual purchase cost | P * D = | 3600 | 3400 | 3200 | 350 | 4005.8571428571 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 350 | 4005.8571428571 | 3802.3571428571 | 3598.8571428571 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| Total Annual Cost | TC = | 3893.9388235294 | 3685.6571428571 | 3480 | 400 | 3972 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 400 | 3972 | 3768 | 3564 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||
| 450 | 3947.6666666667 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 450 | 3947.6666666667 | 3743.1666666667 | 3538.6666666667 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Annual Demand | D = | 4000 | 500 | 3930 | 3725 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 500 | 3930 | 3725 | 3520 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Ordering cost per order | S = | 30 | 550 | 3917.1818181818 | 3711.6818181818 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 550 | 3917.1818181818 | 3711.6818181818 | 3506.1818181818 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost per unit: | H (fixed) = | 600 | 3908 | 3702 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 600 | 3908 | 3702 | 3496 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||
| 2 | FALSE | H (% of price) = | 40.00% | 650 | 3901.6153846154 | 3695.1153846154 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 650 | 3901.6153846154 | 3695.1153846154 | 3488.6153846154 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Optimal Q (overall) | Qopt = | 1000 | 700 | 3897.4285714286 | 3690.4285714286 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 700 | 3897.4285714286 | 3690.4285714286 | 3483.4285714286 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 750 | 3895 | 3687.5 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 750 | 3895 | 3687.5 | 3480 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Actual Order Quantity | Q = | 1000 | 800 | 3894 | 3686 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 800 | 3894 | 3686 | 3478 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Increment | DQ = | 100 | 850 | 3894.1764705882 | 3685.6764705882 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 850 | 3894.1764705882 | 3685.6764705882 | 3477.1764705882 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Price | P = | 0.8 | 900 | 3895.3333333333 | 3686.3333333333 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 900 | 3895.3333333333 | 3686.3333333333 | 3477.3333333333 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Number of orders per year | D/Q = | 4 | 950 | 3897.3157894737 | 3687.8157894737 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 950 | 3897.3157894737 | 3687.8157894737 | 3478.3157894737 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Average Inventory | Q/2 = | 500 | 1000 | 3900 | 3690 | 3480 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1000 | 3900 | 3690 | 3480 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost | (Q/2) * H = | 160 | 1050 | 3903.2857142857 | 3692.7857142857 | 3482.2857142857 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1050 | 3903.2857142857 | 3692.7857142857 | 3482.2857142857 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual ordering cost | (D/Q) * S = | 120 | 1100 | 3907.0909090909 | 3696.0909090909 | 3485.0909090909 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1100 | 3907.0909090909 | 3696.0909090909 | 3485.0909090909 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual purchase cost | P * D = | 3200 | 1150 | 3911.347826087 | 3699.847826087 | 3488.347826087 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1150 | 3911.347826087 | 3699.847826087 | 3488.347826087 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Total Annual Cost | TC = | 3480 | 1200 | 3916 | 3704 | 3492 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1200 | 3916 | 3704 | 3492 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 1250 | 3921 | 3708.5 | 3496 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1250 | 3921 | 3708.5 | 3496 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1300 | 3926.3076923077 | 3713.3076923077 | 3500.3076923077 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1300 | 3926.3076923077 | 3713.3076923077 | 3500.3076923077 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Notes: | Use radio buttons to select holding cost as a fixed amount or as percent of price. | 1350 | 3931.8888888889 | 3718.3888888889 | 3504.8888888889 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1350 | 3931.8888888889 | 3718.3888888889 | 3504.8888888889 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||
| Enter holding cost as a fixed amount in cell E15 or as a percent of price in cell E16. | 1400 | 3937.7142857143 | 3723.7142857143 | 3509.7142857143 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1400 | 3937.7142857143 | 3723.7142857143 | 3509.7142857143 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| ^Top | 1450 | 3943.7586206897 | 3729.2586206897 | 3514.7586206897 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1450 | 3943.7586206897 | 3729.2586206897 | 3514.7586206897 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| 1500 | 3950 | 3735 | 3520 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1500 | 3950 | 3735 | 3520 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1550 | 3956.4193548387 | 3740.9193548387 | 3525.4193548387 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1550 | 3956.4193548387 | 3740.9193548387 | 3525.4193548387 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1600 | 3963 | 3747 | 3531 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1600 | 3963 | 3747 | 3531 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1650 | 3969.7272727273 | 3753.2272727273 | 3536.7272727273 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1650 | 3969.7272727273 | 3753.2272727273 | 3536.7272727273 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1700 | 3976.5882352941 | 3759.5882352941 | 3542.5882352941 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1700 | 3976.5882352941 | 3759.5882352941 | 3542.5882352941 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1750 | 3983.5714285714 | 3766.0714285714 | 3548.5714285714 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1750 | 3983.5714285714 | 3766.0714285714 | 3548.5714285714 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1800 | 3990.6666666667 | 3772.6666666667 | 3554.6666666667 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1800 | 3990.6666666667 | 3772.6666666667 | 3554.6666666667 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1850 | 3997.8648648649 | 3779.3648648649 | 3560.8648648649 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1850 | 3997.8648648649 | 3779.3648648649 | 3560.8648648649 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1900 | 4005.1578947368 | 3786.1578947368 | 3567.1578947368 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1900 | 4005.1578947368 | 3786.1578947368 | 3567.1578947368 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1950 | 4012.5384615385 | 3793.0384615385 | 3573.5384615385 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1950 | 4012.5384615385 | 3793.0384615385 | 3573.5384615385 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2000 | 4020 | 3800 | 3580 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2000 | 4020 | 3800 | 3580 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1000 | 0 | 1000 | 3900 | 3690 | 3480 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||||||||
| 1000 | 3480 | 1000 | 3900 | 3600.7692307692 | 3393.3262123478 | ||||||||||||||||||||||||||
| Start: | 0 | Stop: | 2000 | ||||||||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 5840.9082352941 | ||||||||||||||||||||||||||||
| Steps: | 40 | Step: | 50 | ||||||||||||||||||||||||||||
1 50 100 150 200 250 300 350 400 450 500 550 600 650 700 750 800 850 900 950 1000 1050 1100 1150 1200 1250 1300 1350 1400 1450 1500 1550 1600 1650 1700 1750 1800 1850 1900 1950 2000 1000 1000 0 3480
Order Quantity (Q)
Fixed
Percent of Price
Example 7
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| <Back | ||||||||||||||
| Average demand | d = | 2 | 14 | ERROR:#NUM! | ||||||||||
| Std dev demand | sd = | 0 | 14 | ERROR:#NUM! | ||||||||||
| Average lead time | LT = | 7 | 14 | ERROR:#NUM! | ||||||||||
| Std dev lead time | sLT = | 0 | 14 | ERROR:#NUM! | ||||||||||
| Service level | SL = | 1 | 14 | ERROR:#NUM! | ||||||||||
| Increment | DSL = | 0.01 | 14 | ERROR:#NUM! | ||||||||||
| Stock out risk | 0 | 14 | ERROR:#NUM! | |||||||||||
| Average demand during lead time | dLT = | 14 | 14 | ERROR:#N/A | 14 | ERROR:#NUM! | ||||||||
| Std dev demand during lead time | sdLT = | 0 | 14 | 14 | 14 | ERROR:#NUM! | ||||||||
| z = | ERROR:#N/A | 14 | ERROR:#N/A | 14 | ERROR:#NUM! | |||||||||
| Safety stock | SS = | 0 | 14 | ERROR:#NUM! | ||||||||||
| Reorder point | ROP = | 14 | 14 | 0 | ||||||||||
| 14 | 1 | |||||||||||||
| 14 | 0 | |||||||||||||
| 14 | 1 |
Example 8
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| <Back | ||||||||||||||
| Average demand | d = | 50 | 32.5 | 0.0001745365 | ||||||||||
| Std dev demand | sd = | 5 | 36 | 0.0015830903 | ||||||||||
| Average lead time | LT = | 1 | 39.5 | 0.0087967192 | ||||||||||
| Std dev lead time | sLT = | 0 | 43 | 0.0299454931 | ||||||||||
| Service level | SL = | 0.97 | 46.5 | 0.0624507867 | ||||||||||
| Increment | DSL = | 0.01 | 50 | 0.0797884561 | ||||||||||
| Stock out risk | 0.03 | 53.5 | 0.0624507867 | |||||||||||
| Average demand during lead time | dLT = | 50 | 50 | ERROR:#N/A | 57 | 0.0299454931 | ||||||||
| Std dev demand during lead time | sdLT = | 5 | 50 | 59.4039680408 | 60.5 | 0.0087967192 | ||||||||
| z = | 1.8807936082 | 50 | ERROR:#N/A | 64 | 0.0015830903 | |||||||||
| Safety stock | SS = | 9.4039680408 | 67.5 | 0.0001745365 | ||||||||||
| Reorder point | ROP = | 59.4039680408 | 50 | 0 | ||||||||||
| 50 | 0.0797884561 | |||||||||||||
| 59.4039680408 | 0 | |||||||||||||
| 59.4039680408 | 0.0797884561 |
Example 9
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| <Back | ||||||||||||||
| Average demand | d = | 50 | 85.1507575951 | 0.0002056933 | ||||||||||
| Std dev demand | sd = | 3 | 88.1206060761 | 0.0018656898 | ||||||||||
| Average lead time | LT = | 2 | 91.090454557 | 0.010367033 | ||||||||||
| Std dev lead time | sLT = | 0 | 94.060303038 | 0.0352911021 | ||||||||||
| Service level | SL = | 0.9 | 97.030151519 | 0.0735989579 | ||||||||||
| Increment | DSL = | 0.01 | 100 | 0.0940315973 | ||||||||||
| Stock out risk | 0.1 | 102.969848481 | 0.0735989579 | |||||||||||
| Average demand during lead time | dLT = | 100 | 100 | ERROR:#N/A | 105.939696962 | 0.0352911021 | ||||||||
| Std dev demand during lead time | sdLT = | 4.2426406871 | 100 | 105.4371628146 | 108.909545443 | 0.010367033 | ||||||||
| z = | 1.2815515655 | 100 | ERROR:#N/A | 111.8793939239 | 0.0018656898 | |||||||||
| Safety stock | SS = | 5.4371628146 | 114.8492424049 | 0.0002056933 | ||||||||||
| Reorder point | ROP = | 105.4371628146 | 100 | 0 | ||||||||||
| 100 | 0.0940315973 | |||||||||||||
| 105.4371628146 | 0 | |||||||||||||
| 105.4371628146 | 0.0940315973 |
Example 10
| Fixed Order Interval Model | ||||||||||
| <Back | ||||||||||
| Average demand | d = | 30 | ||||||||
| Std dev demand | sd = | 3 | ||||||||
| Lead time | LT = | 2 | ||||||||
| Amount on hand at reorder time | A = | 71 | ||||||||
| Order interval | OI = | 7 | ||||||||
| Service level | SL = | 0.99 | ||||||||
| Increment | DSL = | 0.01 | ||||||||
| Stock out risk | 0.01 | 199 | 270 | ERROR:#N/A | ERROR:#N/A | |||||
| Average demand during lead time | dLT = | 270 | 199 | 270 | 219.9371308664 | ERROR:#N/A | ||||
| Safety stock | SS = | 20.9371308664 | 199 | 270 | ERROR:#N/A | ERROR:#N/A | ||||
| Amount to order | 219.9371308664 |
Example 11a
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| <Back | ||||||||||||||
| Average demand | d = | 10 | 26 | 0.0002181707 | ||||||||||
| Std dev demand | sd = | 2 | 28.8 | 0.0019788629 | ||||||||||
| Average lead time | LT = | 4 | 31.6 | 0.010995899 | ||||||||||
| Std dev lead time | sLT = | 0 | 34.4 | 0.0374318664 | ||||||||||
| Service level | SL = | 0.7733745074 | 37.2 | 0.0780634833 | ||||||||||
| Increment | DSL = | 0.01 | 40 | 0.0997355701 | ||||||||||
| Stock out risk | 0.2266254926 | 42.8 | 0.0780634833 | |||||||||||
| Average demand during lead time | dLT = | 40 | 40 | ERROR:#N/A | 45.6 | 0.0374318664 | ||||||||
| Std dev demand during lead time | sdLT = | 4 | 40 | 43.0000247037 | 48.4 | 0.010995899 | ||||||||
| z = | 0.7500061759 | 40 | ERROR:#N/A | 51.2 | 0.0019788629 | |||||||||
| Safety stock | SS = | 3.0000247037 | 54 | 0.0002181707 | ||||||||||
| Reorder point | ROP = | 43.0000247037 | 40 | 0 | ||||||||||
| 40 | 0.0997355701 | |||||||||||||
| Note: use Goal Seek to set ROP to 43 by changing SL | 43.0000247037 | 0 | ||||||||||||
| 43.0000247037 | 0.0997355701 |
Example 11b
| Fixed Order Interval Model | ||||||||||
| <Back | ||||||||||
| Average demand | d = | 10 | ||||||||
| Std dev demand | sd = | 2 | ||||||||
| Lead time | LT = | 4 | ||||||||
| Amount on hand at reorder time | A = | 43 | ||||||||
| Order interval | OI = | 12 | ||||||||
| Service level | SL = | 1 | ||||||||
| Increment | DSL = | 0 | ||||||||
| Stock out risk | 0 | 117 | 160 | ERROR:#N/A | ERROR:#N/A | |||||
| Average demand during lead time | dLT = | 160 | 117 | 160 | 125 | ERROR:#N/A | ||||
| Safety stock | SS = | 8 | 117 | 160 | ERROR:#N/A | ERROR:#N/A | ||||
| Amount to order | 125 | |||||||||
| Note: SL = 100% at Q = 125 < 171 |
Example 12
| Single Period Model | ||||||
| <Back | ||||||
| Select demand distribution: | Uniform | |||||
| 1 | ||||||
| Shortage cost (revenue - cost) | Cs = | 0.6 | 0.4 | |||
| Excess cost (cost - salvage) | Ce = | 0.2 | ||||
| Minimum demand | 300 | |||||
| Maximum demand | 500 | |||||
| Optimal Service Level | SLo = | 0.75 | ||||
| Optimal Stocking Level | So = | 450 | ||||
| Actual Stocking Level | S = | 450 | ||||
| Increment | DS = | 10 | ||||
| Actual Service Level | SL = | 0.7500 | ||||
| Balance: | ||||||
| Ce * Service Level | 0.15 | |||||
| Cs * (1 - Service Level) | 0.15 | |||||
| Discrete Distribution: | Demand | Freq | Cum | |||
Uniform
Normal
Poisson
Discrete
Example 13
| Single Period Model | ||||||
| <Back | ||||||
| Select demand distribution: | Normal | |||||
| 2 | ||||||
| Shortage cost (revenue - cost) | Cs = | 0.6 | 0.4 | |||
| Excess cost (cost - salvage) | Ce = | 0.2 | ||||
| Average demand | 200 | |||||
| Std dev demand | 10 | |||||
| Optimal Service Level | SLo = | 0.75 | ||||
| Optimal Stocking Level | So = | 206.744897502 | ||||
| Actual Stocking Level | S = | 207 | ||||
| Increment | DS = | 10 | ||||
| Actual Service Level | SL = | 0.7580 | ||||
| Balance: | ||||||
| Ce * Service Level | 0.1516072696 | |||||
| Cs * (1 - Service Level) | 0.1451781913 | |||||
| Discrete Distribution: | Demand | Freq | Cum | |||
Uniform
Normal
Poisson
Discrete
Example 14
| Single Period Model | ||||||
| <Back | ||||||
| Select demand distribution: | Discrete | |||||
| 4 | ||||||
| Shortage cost (revenue - cost) | Cs = | 4200 | 1600 | |||
| Excess cost (cost - salvage) | Ce = | 800 | ||||
| Optimal Service Level | SLo = | 0.84 | ||||
| So = | ||||||
| Adjust S until SL >= SLo | ||||||
| Actual Stocking Level | S = | 2 | ||||
| Increment | DS = | 1 | ||||
| Actual Service Level | SL = | 0.9000 | ||||
| Balance: | ||||||
| Ce * Service Level | 720 | |||||
| Cs * (1 - Service Level) | 420 | |||||
| Discrete Distribution: | Demand | Freq | Cum | |||
| 0 | 0.2 | 0.2 | ||||
| 1 | 0.4 | 0.6 | ||||
| 2 | 0.3 | 0.9 | ||||
| 3 | 0.1 | 1 | ||||
Uniform
Normal
Poisson
Discrete
Example 15
| Single Period Model | ||||||
| <Back | ||||||
| Select demand distribution: | Poisson | |||||
| 3 | ||||||
| Shortage cost (revenue - cost) | Cs = | 3 | 4 | |||
| Excess cost (cost - salvage) | Ce = | 2 | ||||
| Average demand | 4 | |||||
| Optimal Service Level | SLo = | 0.6 | ||||
| So = | ||||||
| Adjust S until SL >= SLo | ||||||
| Actual Stocking Level | S = | 4 | ||||
| Increment | DS = | 1 | ||||
| Actual Service Level | SL = | 0.6288 | ||||
| Balance: | ||||||
| Ce * Service Level | 1.2576738704 | |||||
| Cs * (1 - Service Level) | 1.1134891945 | |||||
| Discrete Distribution: | Demand | Freq | Cum | |||
Uniform
Normal
Poisson
Discrete
Solved Problem 1
| Basic Economic Order Quantity (EOQ) Model | x | Carry | Order | Total | Q | ||||||||||||||||||||
| <Back | 1 | 1.5 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||||
| Annual Demand | D = | 32000 | 160 | 240 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Ordering cost per order | S = | 120 | 320 | 480 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Annual carrying cost per unit | H = | 3 | 480 | 720 | 8000 | 8720 | |||||||||||||||||||
| Working days per year | D/Y = | 240 | 640 | 960 | 6000 | 6960 | |||||||||||||||||||
| Economic Order Quantity | EOQ = | 1600 | 800 | 1200 | 4800 | 6000 | |||||||||||||||||||
| 960 | 1440 | 4000 | 5440 | ||||||||||||||||||||||
| Actual Order Quantity | Q = | 1600 | 1120 | 1680 | 3428.5714285714 | 5108.5714285714 | |||||||||||||||||||
| Increment | DQ = | 10 | 1280 | 1920 | 3000 | 4920 | |||||||||||||||||||
| Number of orders per year | D/Q = | 20 | 1440 | 2160 | 2666.6666666667 | 4826.6666666667 | |||||||||||||||||||
| Length of order cycle (days) | Q/D = | 12 | 1600 | 2400 | 2400 | 4800 | |||||||||||||||||||
| Average Inventory | Q/2 = | 800 | 1760 | 2640 | 2181.8181818182 | 4821.8181818182 | |||||||||||||||||||
| Annual carrying cost | (Q/2) * H = | 2400 | 1920 | 2880 | 2000 | 4880 | |||||||||||||||||||
| Annual ordering cost | (D/Q) * S = | 2400 | 2080 | 3120 | 1846.1538461539 | 4966.1538461539 | |||||||||||||||||||
| Total Annual Cost | TC = | 4800 | 2240 | 3360 | 1714.2857142857 | 5074.2857142857 | |||||||||||||||||||
| 2400 | 3600 | 1600 | 5200 | ||||||||||||||||||||||
| 2560 | 3840 | 1500 | 5340 | ||||||||||||||||||||||
| 2720 | 4080 | 1411.7647058823 | 5491.7647058824 | ||||||||||||||||||||||
| 2880 | 4320 | 1333.3333333333 | 5653.3333333333 | ||||||||||||||||||||||
| 3040 | 4560 | 1263.1578947368 | 5823.1578947368 | ||||||||||||||||||||||
| 3200 | 4800 | 1200 | 6000 | ||||||||||||||||||||||
| 1600 | 4800 | ||||||||||||||||||||||||
| 1600 | 0 | ||||||||||||||||||||||||
| Start: | 0 | Stop: | 3200 | ||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 9600 | ||||||||||||||||||||||
| Steps: | 20 | Step: | 160 |
1 160 320 480 640 800 960 1120 1280 1440 1600 1760 1920 2080 2240 2400 2560 2720 2880 3040 3200 1600 1600 4800 0
Order Quantity (Q)
Solved Problem 2
| Economic Production Quantity (EPQ) Model | x | Carrying | Setup | Total | Q | ||||||||||||||||||||
| <Back | 1 | 0.75 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||||
| Annual Demand | D = | 11000 | 101.3 | 75.975 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Setup cost | S = | 70 | 202.6 | 151.95 | ERROR:#N/A | ERROR:#N/A | |||||||||||||||||||
| Annual carrying cost per unit | H = | 2 | 303.9 | 227.925 | 2533.7282000658 | 2761.6532000658 | |||||||||||||||||||
| Production rate | p = | 200 | 405.2 | 303.9 | 1900.2961500494 | 2204.1961500494 | |||||||||||||||||||
| Usage rate | u = | 50 | 506.5 | 379.875 | 1520.2369200395 | 1900.1119200395 | |||||||||||||||||||
| Production days per year | D/Y = | 220 | 607.8 | 455.85 | 1266.8641000329 | 1722.7141000329 | |||||||||||||||||||
| Economic Run Quantity | Qp = | 1013 | 709.1 | 531.825 | 1085.8835143139 | 1617.7085143139 | |||||||||||||||||||
| 810.4 | 607.8 | 950.1480750247 | 1557.9480750247 | ||||||||||||||||||||||
| 911.7 | 683.775 | 844.5760666886 | 1528.3510666886 | ||||||||||||||||||||||
| Actual Run Quantity | Q = | 1013 | 1013 | 759.75 | 760.1184600197 | 1519.8684600197 | |||||||||||||||||||
| Increment | DQ = | 100 | 1114.3 | 835.725 | 691.0167818361 | 1526.7417818361 | |||||||||||||||||||
| Number of runs per year | D/Q = | 10.8588351431 | 1215.6 | 911.7 | 633.4320500165 | 1545.1320500164 | |||||||||||||||||||
| Cycle time | Q/u = | 20.26 | 1316.9 | 987.675 | 584.7065077075 | 1572.3815077075 | |||||||||||||||||||
| Run time | Q/p = | 5.065 | 1418.2 | 1063.65 | 542.941757157 | 1606.591757157 | |||||||||||||||||||
| Average Inventory | Iave = | 379.875 | 1519.5 | 1139.625 | 506.7456400132 | 1646.3706400132 | |||||||||||||||||||
| Maximum Inventory | Imax = | 759.75 | 1620.8 | 1215.6 | 475.0740375123 | 1690.6740375123 | |||||||||||||||||||
| Annual carrying cost | Iave * H = | 759.75 | 1722.1 | 1291.575 | 447.128505894 | 1738.703505894 | |||||||||||||||||||
| Annual setup cost | (D/Q) * S = | 760.1184600197 | 1823.4 | 1367.55 | 422.2880333443 | 1789.8380333443 | |||||||||||||||||||
| Total Annual Cost | TC = | 1519.8684600197 | 1924.7 | 1443.525 | 400.0623473788 | 1843.5873473788 | |||||||||||||||||||
| 2026 | 1519.5 | 380.0592300099 | 1899.5592300099 | ||||||||||||||||||||||
| 1013 | 1519.8684600197 | ||||||||||||||||||||||||
| 1013 | 0 | ||||||||||||||||||||||||
| Start: | 0 | Stop: | 2026 | ||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 3546.2369200395 | ||||||||||||||||||||||
| Steps: | 20 | Step: | 101.3 |
1 101.3 202.6 303.89999999999998 405.2 506.5 607.79999999999995 709.09999999999991 810.39999999999986 911.69999999999982 1012.9999999999998 1114.2999999999997 1215.5999999999997 1316.8999999999996 1418.1999999999996 1519.4999999999995 1620.7999999999995 1722.0999999999995 1823.3999999999994 1924.6999999999994 2025.9999999999993 1013 1013 1519.8684600197435 0
Run Quantity (Q)
Solved Problem 3
| Quantity Discounts | 1 | 2 | 3 | 4 | 5 | 6 | 7 | ||||||||||||||||||||||||
| <Back | Notes | Price Level: | 1 | 2 | 3 | 4 | 5 | 6 | 7 | x | 1 | 1000 | 0 | 0 | 0 | 0 | 0 | ||||||||||||||
| Minimum quantity for price | Qmin = | 1 | 1000 | 1 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1 | 350200.255 | 346800.17 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Price | P = | 3.00 | 2.00 | 70.7 | 15027.0808338048 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 70.7 | 15027.0808338048 | 11621.0713338048 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Optimal Q (for each price) | Qopt = | 1155 | 1414 | 141.4 | 12640.5831669024 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 141.4 | 12640.5831669024 | 9228.5641669024 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Number of orders per year | D/Qopt = | 2.9437229437 | 2.4045261669 | 212.1 | 11857.1029446016 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 212.1 | 11857.1029446016 | 8439.0744446016 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Average Inventory | Qopt/2 = | 577.5 | 707 | 282.8 | 11474.3770834512 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 282.8 | 11474.3770834512 | 8050.3390834512 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Annual carrying cost | (Qopt/2) * H = | 294.525 | 240.38 | 353.5 | 11251.952966761 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 353.5 | 11251.952966761 | 7821.905466761 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Annual ordering cost | (D/Qopt) * S = | 294.3722943723 | 240.4526166902 | 424.2 | 11109.6797223008 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 424.2 | 11109.6797223008 | 7673.6227223008 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Annual purchase cost | P * D = | 10200 | 6800 | 494.9 | 11013.2069762578 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 494.9 | 11013.2069762578 | 7571.1404762578 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Total Annual Cost | TC = | 10788.8972943723 | 7280.8326166902 | 565.6 | 10945.3595417256 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 565.6 | 10945.3595417256 | 7497.2835417256 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| 636.3 | 10896.5956482005 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 636.3 | 10896.5956482005 | 7442.5101482005 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Annual Demand | D = | 3400 | 707 | 10861.1902333805 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 707 | 10861.1902333805 | 7401.0952333805 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Ordering cost per order | S = | 100 | 777.7 | 10835.5000758004 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 777.7 | 10835.5000758004 | 7369.3955758004 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost per unit: | H (fixed) = | 848.4 | 10817.0963611504 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 848.4 | 10817.0963611504 | 7344.9823611504 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||
| 2 | FALSE | H (% of price) = | 17.00% | 919.1 | 10804.2976026004 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 919.1 | 10804.2976026004 | 7326.1741026004 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||
| Optimal Q (overall) | Qopt = | 1414 | 989.8 | 10795.9027381289 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 989.8 | 10795.9027381289 | 7311.7697381289 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 1060.5 | 10791.0309889203 | 7300.8884889203 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1060.5 | 10791.0309889203 | 7300.8884889203 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Actual Order Quantity | Q = | 1500 | 1131.2 | 10789.0217708628 | 7292.8697708628 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1131.2 | 10789.0217708628 | 7292.8697708628 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Increment | DQ = | 10 | 1201.9 | 10789.3699314003 | 7287.2084314003 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1201.9 | 10789.3699314003 | 7287.2084314003 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Price | P = | 2 | 1272.6 | 10791.6825741003 | 7283.5115741003 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1272.6 | 10791.6825741003 | 7283.5115741003 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Number of orders per year | D/Q = | 2.2666666667 | 1343.3 | 10795.6495175687 | 7281.4690175687 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1343.3 | 10795.6495175687 | 7281.4690175687 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Average Inventory | Q/2 = | 750 | 1414 | 10801.0226166902 | 7280.8326166902 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1414 | 10801.0226166902 | 7280.8326166902 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual carrying cost | (Q/2) * H = | 255 | 1484.7 | 10807.6009920859 | 7281.4014920859 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1484.7 | 10807.6009920859 | 7281.4014920859 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual ordering cost | (D/Q) * S = | 226.6666666667 | 1555.4 | 10815.2202879002 | 7283.0112879002 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1555.4 | 10815.2202879002 | 7283.0112879002 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Annual purchase cost | P * D = | 6800 | 1626.1 | 10823.7447319046 | 7285.5262319046 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1626.1 | 10823.7447319046 | 7285.5262319046 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| Total Annual Cost | TC = | 7281.6666666667 | 1696.8 | 10833.0611805752 | 7288.8331805752 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1696.8 | 10833.0611805752 | 7288.8331805752 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||
| 1767.5 | 10843.0745933522 | 7292.8370933522 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1767.5 | 10843.0745933522 | 7292.8370933522 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1838.2 | 10853.7045513002 | 7297.4575513002 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1838.2 | 10853.7045513002 | 7297.4575513002 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| Notes: | Use radio buttons to select holding cost as a fixed amount or as percent of price. | 1908.9 | 10864.8825494002 | 7302.6260494002 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1908.9 | 10864.8825494002 | 7302.6260494002 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||
| Enter holding cost as a fixed amount in cell E15 or as a percent of price in cell E16. | 1979.6 | 10876.5498690645 | 7308.2838690645 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 1979.6 | 10876.5498690645 | 7308.2838690645 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| ^Top | 2050.3 | 10888.6558908209 | 7314.3803908209 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2050.3 | 10888.6558908209 | 7314.3803908209 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | |||||||||||||||
| 2121 | 10901.1567444602 | 7320.8717444602 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2121 | 10901.1567444602 | 7320.8717444602 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2191.7 | 10914.0142204453 | 7327.7197204453 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2191.7 | 10914.0142204453 | 7327.7197204453 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2262.4 | 10927.1948854314 | 7334.8908854314 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2262.4 | 10927.1948854314 | 7334.8908854314 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2333.1 | 10940.6693586001 | 7342.3558586001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2333.1 | 10940.6693586001 | 7342.3558586001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2403.8 | 10954.4117157001 | 7350.0887157001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2403.8 | 10954.4117157001 | 7350.0887157001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2474.5 | 10968.3989952516 | 7358.0664952516 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2474.5 | 10968.3989952516 | 7358.0664952516 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2545.2 | 10982.6107870501 | 7366.2687870501 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2545.2 | 10982.6107870501 | 7366.2687870501 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2615.9 | 10997.0288874001 | 7374.6773874001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2615.9 | 10997.0288874001 | 7374.6773874001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2686.6 | 11011.6370087843 | 7383.2760087843 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2686.6 | 11011.6370087843 | 7383.2760087843 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2757.3 | 11026.4205342001 | 7392.0500342001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2757.3 | 11026.4205342001 | 7392.0500342001 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 2828 | 11041.3663083451 | 7400.9863083451 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | 2828 | 11041.3663083451 | 7400.9863083451 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||
| 1500 | 0 | 1500 | 10809.1666666667 | 7281.6666666667 | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ERROR:#N/A | ||||||||||||||||||||||
| 1500 | 7281.6666666667 | 1500 | 10809.1666666667 | 7086.4547837484 | |||||||||||||||||||||||||||
| Start: | 0 | Stop: | 2828 | ||||||||||||||||||||||||||||
| Min Y : | 0 | Max Y: | 16183.3459415584 | ||||||||||||||||||||||||||||
| Steps: | 40 | Step: | 70.7 | ||||||||||||||||||||||||||||
1 70.7 141.4 212.10000000000002 282.8 353.5 424.2 494.9 565.6 636.30000000000007 707.00000000000011 777.70000000000016 848.4000000000002 919.10000000000025 989.8000000000003 1060.5000000000002 1131.2000000000003 1201.9000000000003 1272.6000000000004 1343.3000000000004 1414.0000000000005 1484.7000000000005 1555.4000000000005 1626.1000000000006 1696.8000000000006 1767.5000000000007 1838.2000000000007 1908.9000000000008 1979.6000000000008 2050.3000000000006 2121.0000000000005 2191.7000000000003 2262.4 2333.1 2403.7999999999997 2474.4999999999995 2545.1999999999994 2615.8999999999992 2686.599999999999 2757.2999999999988 2827.9999999999986 1500 1500 0 7281.666666666667
Order Quantity (Q)
Fixed
Percent of Price
Solved Problem 4
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| <Back | ||||||||||||||
| Average demand | d = | 400 | 1145.4403995616 | 0.0000559826 | ||||||||||
| Std dev demand | sd = | 9 | 1156.3523196493 | 0.0005077765 | ||||||||||
| Average lead time | LT = | 3 | 1167.264239737 | 0.002821549 | ||||||||||
| Std dev lead time | sLT = | 0 | 1178.1761598246 | 0.0096050214 | ||||||||||
| Service level | SL = | 0.98 | 1189.0880799123 | 0.0200310992 | ||||||||||
| Increment | DSL = | 0.01 | 1200 | 0.0255921592 | ||||||||||
| Stock out risk | 0.02 | 1210.9119200877 | 0.0200310992 | |||||||||||
| Average demand during lead time | dLT = | 1200 | 1200 | ERROR:#N/A | 1221.8238401754 | 0.0096050214 | ||||||||
| Std dev demand during lead time | sdLT = | 15.5884572681 | 1200 | 1232.0147771328 | 1232.735760263 | 0.002821549 | ||||||||
| z = | 2.0537489106 | 1200 | ERROR:#N/A | 1243.6476803507 | 0.0005077765 | |||||||||
| Safety stock | SS = | 32.0147771328 | 1254.5596004384 | 0.0000559826 | ||||||||||
| Reorder point | ROP = | 1232.0147771328 | 1200 | 0 | ||||||||||
| 1200 | 0.0255921592 | |||||||||||||
| 1232.0147771328 | 0 | |||||||||||||
| 1232.0147771328 | 0.0255921592 |
Solved Problem 5
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| <Back | ||||||||||||||
| Average demand | d = | 600 | -600 | 0.0000007272 | ||||||||||
| Std dev demand | sd = | 0 | 240 | 0.0000065962 | ||||||||||
| Average lead time | LT = | 6 | 1080 | 0.000036653 | ||||||||||
| Std dev lead time | sLT = | 2 | 1920 | 0.0001247729 | ||||||||||
| Service level | SL = | 0.9 | 2760 | 0.0002602116 | ||||||||||
| Increment | DSL = | 0.01 | 3600 | 0.0003324519 | ||||||||||
| Stock out risk | 0.1 | 4440 | 0.0002602116 | |||||||||||
| Average demand during lead time | dLT = | 3600 | 3600 | ERROR:#N/A | 5280 | 0.0001247729 | ||||||||
| Std dev demand during lead time | sdLT = | 1200 | 3600 | 5137.8618786535 | 6120 | 0.000036653 | ||||||||
| z = | 1.2815515655 | 3600 | ERROR:#N/A | 6960 | 0.0000065962 | |||||||||
| Safety stock | SS = | 1537.8618786535 | 7800 | 0.0000007272 | ||||||||||
| Reorder point | ROP = | 5137.8618786535 | 3600 | 0 | ||||||||||
| 3600 | 0.0003324519 | |||||||||||||
| 5137.8618786535 | 0 | |||||||||||||
| b. | ROP / d = | 8.5631031311 | 5137.8618786535 | 0.0003324519 |
Solved Problem 6
| Reorder Point (ROP) with EOQ Ordering | ||||||||||||||
| <Back | ||||||||||||||
| Average demand | d = | 25 | 71.8778509 | 0.0000171477 | ||||||||||
| Std dev demand | sd = | 3 | 107.50228072 | 0.0001555342 | ||||||||||
| Average lead time | LT = | 10 | 143.12671054 | 0.0008642529 | ||||||||||
| Std dev lead time | sLT = | 2 | 178.75114036 | 0.0029420604 | ||||||||||
| Service level | SL = | 0.95 | 214.37557018 | 0.0061356141 | ||||||||||
| Increment | DSL = | 0.01 | 250 | 0.0078389913 | ||||||||||
| Stock out risk | 0.05 | 285.62442982 | 0.0061356141 | |||||||||||
| Average demand during lead time | dLT = | 250 | 250 | ERROR:#N/A | 321.24885964 | 0.0029420604 | ||||||||
| Std dev demand during lead time | sdLT = | 50.8920426 | 250 | 333.7099608536 | 356.87328946 | 0.0008642529 | ||||||||
| z = | 1.644853627 | 250 | ERROR:#N/A | 392.49771928 | 0.0001555342 | |||||||||
| Safety stock | SS = | 83.7099608536 | 428.1221491 | 0.0000171477 | ||||||||||
| Reorder point | ROP = | 333.7099608536 | 250 | 0 | ||||||||||
| 250 | 0.0078389913 | |||||||||||||
| 333.7099608536 | 0 | |||||||||||||
| 333.7099608536 | 0.0078389913 |
Solved Problem 7
| Fixed Order Interval Model | ||||||||||
| <Back | ||||||||||
| Average demand | d = | 15.2 | ||||||||
| Std dev demand | sd = | 1.6 | ||||||||
| Lead time | LT = | 5 | ||||||||
| Amount on hand at reorder time | A = | 275 | ||||||||
| Order interval | OI = | 30 | ||||||||
| Service level | SL = | 0.95 | ||||||||
| Increment | DSL = | 0.01 | ||||||||
| Stock out risk | 0.05 | 257 | 532 | ERROR:#N/A | ERROR:#N/A | |||||
| Average demand during lead time | dLT = | 532 | 257 | 532 | 272.5697364617 | ERROR:#N/A | ||||
| Safety stock | SS = | 15.5697364617 | 257 | 532 | ERROR:#N/A | ERROR:#N/A | ||||
| Amount to order | 272.5697364617 |
Solved Problem 8
| Single Period Model | ||||||
| <Back | ||||||
| Select demand distribution: | Poisson | |||||
| 3 | ||||||
| Shortage cost (revenue - cost) | Cs = | 341.347988 | 682.695976 | |||
| Excess cost (cost - salvage) | Ce = | 500 | ||||
| Average demand | 2 | |||||
| Optimal Service Level | SLo = | 0.4057155813 | ||||
| So = | ||||||
| Adjust S until SL >= SLo | ||||||
| Actual Stocking Level | S = | 1 | ||||
| Increment | DS = | 1 | ||||
| Actual Service Level | SL = | 0.4060 | ||||
| Balance: | ||||||
| Ce * Service Level | 203.0029248549 | |||||
| Cs * (1 - Service Level) | 202.7587080853 | |||||
| Discrete Distribution: | Demand | Freq | Cum | |||
| Note: For S = 1, Actual Service Level = .4060 so use Goal Seek | ||||||
| to set SLo to .406 by changing Cs, then set S = 2 and repeat. | ||||||
Uniform
Normal
Poisson
Discrete
Problems 1-10
| Chapter 13 - Problems 1-10 | Note: This worksheet displays results only, you must copy the shaded | ||||
| <Back | area into the corresponding template to make additional calculations. | ||||
| 1a. | ABC Classification System | ||||
| Dollar Amount | Number of Items | ||||
| Class | Total | Percent | Total | Percent | |
| A | 5,100 | 41.91% | 1 | 16.67% | |
| B | 4,900 | 40.26% | 2 | 33.33% | |
| C | 2,170 | 17.83% | 3 | 50.00% | |
| Enter lower limit for dollar amount: | |||||
| A | 5,100 | B | 2,400 | ||
| Unit | Dollar | ||||
| Item | Usage | Cost | Amount | Class | |
| 1 | 25 | 100 | 2,500 | B | |
| 2 | 30 | 80 | 2,400 | B | |
| 3 | 60 | 15 | 900 | C | |
| 4 | 10 | 50 | 500 | C | |
| 5 | 70 | 11 | 770 | C | |
| 6 | 85 | 60 | 5,100 | A | |
| 1b. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 4500 | |||
| Ordering cost per order | S = | 36 | |||
| Annual carrying cost per unit | H = | 10 | |||
| Working days per year | D/Y = | 240 | |||
| Economic Order Quantity | EOQ = | 180 | |||
| Actual Order Quantity | Q = | 300 | |||
| Increment | DQ = | 10 | |||
| Number of orders per year | D/Q = | 15 | |||
| Length of order cycle (days) | Q/D = | 16 | |||
| Average Inventory | Q/2 = | 150 | |||
| Annual carrying cost | (Q/2) * H = | 1500 | |||
| Annual ordering cost | (D/Q) * S = | 540 | |||
| Total Annual Cost | TC = | 2040 | |||
| 1c. | Economic Production Quantity (EPQ) Model | ||||
| Annual Demand | D = | 18000 | |||
| Setup cost | S = | 100 | |||
| Annual carrying cost per unit | H = | 40 | |||
| Production rate | p = | 120 | |||
| Usage rate | u = | 90 | |||
| Production days per year | D/Y = | 240 | |||
| Economic Run Quantity | Qp = | 600 | |||
| Actual Run Quantity | Q = | 2400 | |||
| Increment | DQ = | 100 | |||
| Number of runs per year | D/Q = | 7.5 | |||
| Cycle time | Q/u = | 32 | |||
| Run time | Q/p = | 20 | |||
| Average Inventory | Iave = | 300 | |||
| Maximum Inventory | Imax = | 600 | |||
| Annual carrying cost | Iave * H = | 12000 | |||
| Annual setup cost | (D/Q) * S = | 750 | |||
| Total Annual Cost | TC = | 12750 | |||
| 2a. | ABC Classification System | ||||
| Dollar Amount | Number of Items | ||||
| Class | Total | Percent | Total | Percent | |
| A | 55,000 | 58.43% | 3 | 18.75% | |
| B | 29,700 | 31.55% | 5 | 31.25% | |
| C | 9,430 | 10.02% | 8 | 50.00% | |
| Enter lower limit for dollar amount: | |||||
| A | 15,000 | B | 4,800 | ||
| Unit | Dollar | ||||
| Item | Usage | Cost | Amount | Class | |
| K34 | 10 | 200 | 2,000 | C | |
| K35 | 25 | 600 | 15,000 | A | |
| K36 | 36 | 150 | 5,400 | B | |
| M10 | 16 | 25 | 400 | C | |
| M20 | 20 | 80 | 1,600 | C | |
| Z45 | 80 | 200 | 16,000 | A | |
| F14 | 20 | 300 | 6,000 | B | |
| F95 | 30 | 800 | 24,000 | A | |
| F99 | 20 | 60 | 1,200 | C | |
| D45 | 10 | 550 | 5,500 | B | |
| D48 | 12 | 90 | 1,080 | C | |
| D52 | 15 | 110 | 1,650 | C | |
| D57 | 40 | 120 | 4,800 | B | |
| N08 | 30 | 40 | 1,200 | C | |
| P05 | 16 | 500 | 8,000 | B | |
| P09 | 10 | 30 | 300 | C | |
| 2b. | ABC Classification System | ||||
| Dollar Amount | Number of Items | ||||
| Class | Total | Percent | Total | Percent | |
| A | 126,000 | 55.26% | 1 | 11.11% | |
| B | 66,000 | 28.95% | 3 | 33.33% | |
| C | 36,000 | 15.79% | 5 | 55.56% | |
| Enter lower limit for dollar amount: | |||||
| A | 126,000 | B | 20,000 | ||
| Unit | Dollar | ||||
| Item | Usage | Cost | Amount | Class | |
| 4021 | 90 | 1,400 | 126,000 | A | |
| 9402 | 300 | 12 | 3,600 | C | |
| 4066 | 30 | 700 | 21,000 | B | |
| 6500 | 150 | 20 | 3,000 | C | |
| 9280 | 10 | 1,020 | 10,200 | C | |
| 4050 | 80 | 140 | 11,200 | C | |
| 6850 | 2,000 | 10 | 20,000 | B | |
| 3010 | 400 | 20 | 8,000 | C | |
| 4400 | 5,000 | 5 | 25,000 | B | |
| 3. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 1215 | |||
| Ordering cost per order | S = | 10 | |||
| Annual carrying cost per unit | H = | 75 | |||
| Working days per year | D/Y = | 240 | |||
| Economic Order Quantity | EOQ = | 18 | |||
| Actual Order Quantity | Q = | 18 | |||
| Increment | DQ = | 10 | |||
| Number of orders per year | D/Q = | 67.5 | |||
| Length of order cycle (days) | Q/D = | 3.5555555556 | |||
| Average Inventory | Q/2 = | 9 | |||
| Annual carrying cost | (Q/2) * H = | 675 | |||
| Annual ordering cost | (D/Q) * S = | 675 | |||
| Total Annual Cost | TC = | 1350 | |||
| For part d, if Q remains at 18 then TAC goes up by 81, | |||||
| if Q is decreased to 17 (new EOQ) then TAC goes up by 78.71. | |||||
| 4. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 10400 | |||
| Ordering cost per order | S = | 60 | |||
| Annual carrying cost per unit | H = | 30 | |||
| Working days per year | D/Y = | 260 | |||
| Economic Order Quantity | EOQ = | 203.9607805437 | |||
| Actual Order Quantity | Q = | 204 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 50.9803921569 | |||
| Length of order cycle (days) | Q/D = | 5.1 | |||
| Average Inventory | Q/2 = | 102 | |||
| Annual carrying cost | (Q/2) * H = | 3060 | |||
| Annual ordering cost | (D/Q) * S = | 3058.8235294118 | |||
| Total Annual Cost | TC = | 6118.8235294118 | |||
| 4d. | Actual Order Quantity | Q = | 200 | ||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 52 | |||
| Length of order cycle (days) | Q/D = | 5 | |||
| Average Inventory | Q/2 = | 100 | |||
| Annual carrying cost | (Q/2) * H = | 3000 | |||
| Annual ordering cost | (D/Q) * S = | 3120 | |||
| Total Annual Cost | TC = | 6120 | |||
| 5. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 9000 | |||
| Ordering cost per order | S = | 20 | |||
| Annual carrying cost per unit | H = | 0.6 | |||
| Working days per year | D/Y = | 260 | |||
| Economic Order Quantity | EOQ = | 774.5966692415 | |||
| Actual Order Quantity | Q = | 775 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 11.6129032258 | |||
| Length of order cycle (days) | Q/D = | 22.3888888889 | |||
| Average Inventory | Q/2 = | 387.5 | |||
| Annual carrying cost | (Q/2) * H = | 232.5 | |||
| Annual ordering cost | (D/Q) * S = | 232.2580645161 | |||
| Total Annual Cost | TC = | 464.7580645161 | |||
| Actual Order Quantity | Q = | 1500 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 6 | |||
| Length of order cycle (days) | Q/D = | 43.3333333333 | |||
| Average Inventory | Q/2 = | 750 | |||
| Annual carrying cost | (Q/2) * H = | 450 | |||
| Annual ordering cost | (D/Q) * S = | 120 | |||
| Total Annual Cost | TC = | 570 | |||
| 6. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 9600 | |||
| Ordering cost per order | S = | 28 | |||
| Annual carrying cost per unit | H = | 3.5 | |||
| Working days per year | D/Y = | 360 | |||
| Economic Order Quantity | EOQ = | 391.9183588453 | |||
| Actual Order Quantity | Q = | 392 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 24.4897959184 | |||
| Length of order cycle (days) | Q/D = | 14.7 | |||
| Average Inventory | Q/2 = | 196 | |||
| Annual carrying cost | (Q/2) * H = | 686 | |||
| Annual ordering cost | (D/Q) * S = | 685.7142857143 | |||
| Total Annual Cost | TC = | 1371.7142857143 | |||
| Actual Order Quantity | Q = | 800 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 12 | |||
| Length of order cycle (days) | Q/D = | 30 | |||
| Average Inventory | Q/2 = | 400 | |||
| Annual carrying cost | (Q/2) * H = | 1400 | |||
| Annual ordering cost | (D/Q) * S = | 336 | |||
| Total Annual Cost | TC = | 1736 | |||
| 7a. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 100 | |||
| Ordering cost per order | S = | 55 | |||
| Annual carrying cost per unit | H = | 2 | |||
| Working days per year | D/Y = | 360 | |||
| Economic Order Quantity | EOQ = | 74.161984871 | |||
| Actual Order Quantity | Q = | 75 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 1.3333333333 | |||
| Length of order cycle (days) | Q/D = | 270 | |||
| Average Inventory | Q/2 = | 37.5 | |||
| Annual carrying cost | (Q/2) * H = | 75 | |||
| Annual ordering cost | (D/Q) * S = | 73.3333333333 | |||
| Total Annual Cost | TC = | 148.3333333333 | |||
| Basic Economic Order Quantity (EOQ) Model | |||||
| Annual Demand | D = | 150 | |||
| Ordering cost per order | S = | 55 | |||
| Annual carrying cost per unit | H = | 2 | |||
| Working days per year | D/Y = | 360 | |||
| Economic Order Quantity | EOQ = | 90.8295106229 | |||
| Actual Order Quantity | Q = | 91 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 1.6483516484 | |||
| Length of order cycle (days) | Q/D = | 218.4 | |||
| Average Inventory | Q/2 = | 45.5 | |||
| Annual carrying cost | (Q/2) * H = | 91 | |||
| Annual ordering cost | (D/Q) * S = | 90.6593406593 | |||
| Total Annual Cost | TC = | 181.6593406593 | |||
| 7c. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 100 | |||
| Ordering cost per order | S = | 45 | |||
| Annual carrying cost per unit | H = | 2 | |||
| Working days per year | D/Y = | 360 | |||
| Economic Order Quantity | EOQ = | 67.082039325 | |||
| Actual Order Quantity | Q = | 50 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 2 | |||
| Length of order cycle (days) | Q/D = | 180 | |||
| Average Inventory | Q/2 = | 25 | |||
| Annual carrying cost | (Q/2) * H = | 50 | |||
| Annual ordering cost | (D/Q) * S = | 90 | |||
| Total Annual Cost | TC = | 140 | |||
| Basic Economic Order Quantity (EOQ) Model | |||||
| Annual Demand | D = | 150 | |||
| Ordering cost per order | S = | 45 | |||
| Annual carrying cost per unit | H = | 2 | |||
| Working days per year | D/Y = | 360 | |||
| Economic Order Quantity | EOQ = | 82.1583836258 | |||
| Actual Order Quantity | Q = | 100 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 1.5 | |||
| Length of order cycle (days) | Q/D = | 240 | |||
| Average Inventory | Q/2 = | 50 | |||
| Annual carrying cost | (Q/2) * H = | 100 | |||
| Annual ordering cost | (D/Q) * S = | 67.5 | |||
| Total Annual Cost | TC = | 167.5 | |||
| 8a. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 27000 | |||
| Ordering cost per order | S = | 60 | |||
| Annual carrying cost per unit | H = | 0.18 | |||
| Working days per year | D/Y = | 20 | |||
| Economic Order Quantity | EOQ = | 4242.6406871193 | |||
| Actual Order Quantity | Q = | 4243 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 6.363422107 | |||
| Length of order cycle (days) | Q/D = | 3.142962963 | |||
| Average Inventory | Q/2 = | 2121.5 | |||
| Annual carrying cost | (Q/2) * H = | 381.87 | |||
| Annual ordering cost | (D/Q) * S = | 381.80532642 | |||
| Total Annual Cost | TC = | 763.67532642 | |||
| Actual Order Quantity | Q = | 4000 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 6.75 | |||
| Length of order cycle (days) | Q/D = | 2.962962963 | |||
| Average Inventory | Q/2 = | 2000 | |||
| Annual carrying cost | (Q/2) * H = | 360 | |||
| Annual ordering cost | (D/Q) * S = | 405 | |||
| Total Annual Cost | TC = | 765 | |||
| 8b. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 27000 | |||
| Ordering cost per order | S = | 24.3000000279 | |||
| Annual carrying cost per unit | H = | 0.18 | |||
| Working days per year | D/Y = | 20 | |||
| Economic Order Quantity | EOQ = | 2700.0000015504 | |||
| Actual Order Quantity | Q = | 2700 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 10 | |||
| Length of order cycle (days) | Q/D = | 2 | |||
| Average Inventory | Q/2 = | 1350 | |||
| Annual carrying cost | (Q/2) * H = | 243 | |||
| Annual ordering cost | (D/Q) * S = | 243.0000002791 | |||
| Total Annual Cost | TC = | 486.0000002791 | |||
| Note: use Goal Seek to set EOQ=2700 by changing S. | |||||
| 8c. | Basic Economic Order Quantity (EOQ) Model | ||||
| Annual Demand | D = | 27000 | |||
| Ordering cost per order | S = | 50 | |||
| Annual carrying cost per unit | H = | 0.18 | |||
| Working days per year | D/Y = | 20 | |||
| Economic Order Quantity | EOQ = | 3872.9833462074 | |||
| Actual Order Quantity | Q = | 2700 | |||
| Increment | DQ = | 1 | |||
| Number of orders per year | D/Q = | 10 | |||
| Length of order cycle (days) | Q/D = | 2 | |||
| Average Inventory | Q/2 = | 1350 | |||
| Annual carrying cost | (Q/2) * H = | 243 | |||
| Annual ordering cost | (D/Q) * S = | 500 | |||
| Total Annual Cost | TC = | 743 | |||
| Justification: carry less inventory. | |||||
| 9. | Economic Production Quantity (EPQ) Model | ||||
| Annual Demand | D = | 75000 | |||
| Setup cost | S = | 22 | |||
| Annual carrying cost per unit | H = | 0.15 | |||
| Production rate | p = | 5000 | |||
| Usage rate | u = | 250 | |||
| Production days per year | D/Y = | 300 | |||
| Economic Run Quantity | Qp = | 4812 | |||
| Actual Run Quantity | Q = | 4812 | |||
| Increment | DQ = | 100 | |||
| Number of runs per year | D/Q = | 15.5860349127 | |||
| Cycle time | Q/u = | 19.248 | |||
| Run time | Q/p = | 0.9624 | |||
| Average Inventory | Iave = | 2285.7 | |||
| Maximum Inventory | Imax = | 4571.4 | |||
| Annual carrying cost | Iave * H = | 342.855 | |||
| Annual setup cost | (D/Q) * S = | 342.8927680798 | |||
| Total Annual Cost | TC = | 685.7477680798 | |||
| 10. | Economic Production Quantity (EPQ) Model | ||||
| Annual Demand | D = | 80000 | |||
| Setup cost | S = | 100 | |||
| Annual carrying cost per unit | H = | 0.25 | |||
| Production rate | p = | 1000 | |||
| Usage rate | u = | 400 | |||
| Production days per year | D/Y = | 200 | |||
| Economic Run Quantity | Qp = | 10328 | |||
| Actual Run Quantity | Q = | 10328 | |||
| Increment | DQ = | 100 | |||
| Number of runs per year | D/Q = | 7.745933385 | |||
| Cycle time | Q/u = | 25.82 | |||
| Run time | Q/p = | 10.328 | |||
| Average Inventory | Iave = | 3098.4 | |||
| Maximum Inventory | Imax = | 6196.8 | |||
| Annual carrying cost | Iave * H = | 774.6 | |||
| Annual setup cost | (D/Q) * S = | 774.5933384973 | |||
| Total Annual Cost | TC = | 1549.1933384973 | |||
| Note: D, H, p, and u have been expressed in bags, not tons. | |||||
| 10e. | Annual Demand | D = | 80000 | ||
| Setup cost | S = | 25 | |||
| Annual carrying cost per unit | H = | 0.25 | |||
| Production rate | p = | 1000 | |||
| Usage rate | u = | 400 | |||
| Production days per year | D/Y = | 200 | |||
| Economic Run Quantity | Qp = | 5164 | |||
| Actual Run Quantity | Q = | 5164 | |||
| Increment | DQ = | 100 | |||
| Number of runs per year | D/Q = | 15.4918667699 | |||
| Cycle time | Q/u = | 12.91 | |||
| Run time | Q/p = | 5.164 | |||
| Average Inventory | Iave = | 1549.2 | |||
| Maximum Inventory | Imax = | 3098.4 | |||
| Annual carrying cost | Iave * H = | 387.3 | |||
| Annual setup cost | (D/Q) * S = | 387.2966692486 | |||
| Total Annual Cost | TC = | 774.5966692486 | |||
| Savings = | 774.5966692486 |
Problems 11-20
| Chapter 13 - Problems 11-20 | Note: This worksheet displays results only, you must copy the shaded | |||||||
| <Back | area into the corresponding template to make additional calculations. | |||||||
| 11. | Economic Production Quantity (EPQ) Model | |||||||
| Annual Demand | D = | 20000 | ||||||
| Setup cost | S = | 60 | ||||||
| Annual carrying cost per unit | H = | 2 | ||||||
| Production rate | p = | 200 | ||||||
| Usage rate | u = | 80 | ||||||
| Production days per year | D/Y = | 250 | ||||||
| Economic Run Quantity | Qp = | 1414 | ||||||
| Actual Run Quantity | Q = | 1414 | ||||||
| Increment | FALSE | DQ = | 100 | |||||
| Number of runs per year | D/Q = | 14.14427157 | ||||||
| Cycle time | Q/u = | 17.675 | ||||||
| Run time | Q/p = | 7.07 | ||||||
| Average Inventory | Iave = | 424.2 | ||||||
| Maximum Inventory | Imax = | 848.4 | ||||||
| Annual carrying cost | Iave * H = | 848.4 | ||||||
| Annual setup cost | (D/Q) * S = | 848.6562942008 | ||||||
| Total Annual Cost | TC = | 1697.0562942009 | ||||||
| c. | p - u = | 120 | ||||||
| d. | Cycle time - Run Time - 1 = | 9.605 | ||||||
| 11f. | Economic Production Quantity (EPQ) Model | |||||||
| Annual Demand | D = | 20000 | ||||||
| Setup cost | S = | 60 | ||||||
| Annual carrying cost per unit | H = | 2 | ||||||
| Production rate | p = | 200 | ||||||
| Usage rate | u = | 80 | ||||||
| Production days per year | D/Y = | 250 | ||||||
| Economic Run Quantity | Qp = | 1414 | ||||||
| Actual Run Quantity | Q = | 1466.6666666667 | 52.6666666667 | |||||
| Increment | DQ = | 100 | ||||||
| Number of runs per year | D/Q = | 13.6363636364 | ||||||
| Cycle time | Q/u = | 18.3333333333 | 0.6583333333 | |||||
| Run time | Q/p = | 7.3333333333 | 0.2633333333 | |||||
| Average Inventory | Iave = | 440 | ||||||
| Maximum Inventory | Imax = | 880 | ||||||
| Annual carrying cost | Iave * H = | 880 | ||||||
| Annual setup cost | (D/Q) * S = | 818.1818181818 | ||||||
| Total Annual Cost | TC = | 1698.1818181818 | 1.125523981 | |||||
| f. | Use Goal seek to set the following formula to 10 bychanging Q | |||||||
| Available time = Cycle time - Run Time - Set-up time | ||||||||
| = | 10 | |||||||
| additional units = | 52.6666666667 | |||||||
| additional cost = | 1.125523981 | |||||||
| 13. | Quantity Discounts | |||||||
| Price Level: | 1 | 2 | 3 | 4 | ||||
| Minimum quantity for price | Qmin = | 1000 | 2000 | 5000 | 10000 | |||
| Price | P = | 1.25 | 1.20 | 1.18 | 1.15 | |||
| Optimal Q (for each price) | Qopt = | 2400 | 2400 | 5000 | 10000 | |||
| Number of orders per year | D/Qopt = | 7.5 | 7.5 | 3.6 | 1.8 | |||
| Average Inventory | Qopt/2 = | 1200 | 1200 | 2500 | 5000 | |||
| Annual carrying cost | (Qopt/2) * H = | 240 | 240 | 500 | 1000 | |||
| Annual ordering cost | (D/Qopt) * S = | 240 | 240 | 115.2 | 57.6 | |||
| Annual purchase cost | P * D = | 22500 | 21600 | 21240 | 20700 | |||
| Total Annual Cost | TC = | 22980 | 22080 | 21855.2 | 21757.6 | |||
| Annual Demand | D = | 18000 | ||||||
| Ordering cost per order | S = | 32 | ||||||
| Annual carrying cost per unit: | H (fixed) = | 0.2 | ||||||
| 1 | TRUE | H (% of price) = | ||||||
| Optimal Q (overall) | Qopt = | 10000 | ||||||
| Actual Order Quantity | Q = | 10000 | ||||||
| Increment | DQ = | 100 | ||||||
| Price | P = | 1.15 | ||||||
| Number of orders per year | D/Q = | 1.8 | ||||||
| Average Inventory | Q/2 = | 5000 | ||||||
| Annual carrying cost | (Q/2) * H = | 1000 | ||||||
| Annual ordering cost | (D/Q) * S = | 57.6 | ||||||
| Annual purchase cost | P * D = | 20700 | ||||||
| Total Annual Cost | TC = | 21757.6 | ||||||
| 14a. | Quantity Discounts | |||||||
| Price Level: | 1 | 2 | 3 | |||||
| Minimum quantity for price | Qmin = | 1 | 400 | 600 | ||||
| Price | P = | 10.00 | 9.00 | 8.00 | ||||
| Optimal Q (for each price) | Qopt = | 490 | 490 | 600 | ||||
| Number of orders per year | D/Qopt = | 10.2040816327 | 10.2040816327 | 8.3333333333 | ||||
| Average Inventory | Qopt/2 = | 245 | 245 | 300 | ||||
| Annual carrying cost | (Qopt/2) * H = | 490 | 490 | 600 | ||||
| Annual ordering cost | (D/Qopt) * S = | 489.7959183673 | 489.7959183673 | 400 | ||||
| Annual purchase cost | P * D = | 50000 | 45000 | 40000 | ||||
| Total Annual Cost | TC = | 50979.7959183673 | 45979.7959183673 | 41000 | ||||
| Annual Demand | D = | 5000 | ||||||
| Ordering cost per order | S = | 48 | ||||||
| Annual carrying cost per unit: | H (fixed) = | 2 | ||||||
| 1 | TRUE | H (% of price) = | ||||||
| Optimal Q (overall) | Qopt = | 600 | ||||||
| Actual Order Quantity | Q = | 600 | ||||||
| Increment | DQ = | 10 | ||||||
| Price | P = | 8 | ||||||
| Number of orders per year | D/Q = | 8.3333333333 | ||||||
| Average Inventory | Q/2 = | 300 | ||||||
| Annual carrying cost | (Q/2) * H = | 600 | ||||||
| Annual ordering cost | (D/Q) * S = | 400 | ||||||
| Annual purchase cost | P * D = | 40000 | ||||||
| Total Annual Cost | TC = | 41000 | ||||||
| Price Level: | 1 | 2 | 3 | |||||
| 14b. | Minimum quantity for price | Qmin = | 1 | 400 | 600 | |||
| Price | P = | 10.00 | 9.00 | 8.00 | ||||
| Optimal Q (for each price) | Qopt = | 400 | 422 | 600 | ||||
| Number of orders per year | D/Qopt = | 12.5 | 11.8483412322 | 8.3333333333 | ||||
| Average Inventory | Qopt/2 = | 200 | 211 | 300 | ||||
| Annual carrying cost | (Qopt/2) * H = | 600 | 569.7 | 720 | ||||
| Annual ordering cost | (D/Qopt) * S = | 600 | 568.7203791469 | 400 | ||||
| Annual purchase cost | P * D = | 50000 | 45000 | 40000 | ||||
| Total Annual Cost | TC = | 51200 | 46138.4203791469 | 41120 | ||||
| Annual Demand | D = | 5000 | ||||||
| Ordering cost per order | S = | 48 | ||||||
| Annual carrying cost per unit: | H (fixed) = | |||||||
| 2 | FALSE | H (% of price) = | 30.00% | |||||
| Optimal Q (overall) | Qopt = | 600 | ||||||
| Actual Order Quantity | Q = | 600 | ||||||
| Increment | DQ = | 10 | ||||||
| Price | P = | 8 | ||||||
| Number of orders per year | D/Q = | 8.3333333333 | ||||||
| Average Inventory | Q/2 = | 300 | ||||||
| Annual carrying cost | (Q/2) * H = | 720 | ||||||
| Annual ordering cost | (D/Q) * S = | 400 | ||||||
| Annual purchase cost | P * D = | 40000 | ||||||
| Total Annual Cost | TC = | 41120 | ||||||
| 15. | Minimum quantity for price | Qmin = | 1 | 1000 | 4000 | 6000 | ||
| Price | P = | 5.00 | 4.95 | 4.90 | 4.85 | |||
| Optimal Q (for each price) | Qopt = | 495 | 1000 | 4000 | 6000 | |||
| Number of orders per year | D/Qopt = | 9.898989899 | 4.9 | 1.225 | 0.8166666667 | |||
| Average Inventory | Qopt/2 = | 247.5 | 500 | 2000 | 3000 | |||
| Annual carrying cost | (Qopt/2) * H = | 495 | 990 | 3920 | 5820 | |||
| Annual ordering cost | (D/Qopt) * S = | 494.9494949495 | 245 | 61.25 | 40.8333333333 | |||
| Annual purchase cost | P * D = | 24500 | 24255 | 24010 | 23765 | |||
| Total Annual Cost | TC = | 25489.9494949495 | 25490 | 27991.25 | 29625.8333333333 | |||
| Annual Demand | D = | 4900 | ||||||
| Ordering cost per order | S = | 50 | ||||||
| Annual carrying cost per unit: | H (fixed) = | |||||||
| 2 | FALSE | H (% of price) = | 40.00% | |||||
| Optimal Q (overall) | Qopt = | 495 | ||||||
| Actual Order Quantity | Q = | 495 | ||||||
| Increment | DQ = | 10 | ||||||
| Price | P = | 5 | ||||||
| Number of orders per year | D/Q = | 9.898989899 | ||||||
| Average Inventory | Q/2 = | 247.5 | ||||||
| Annual carrying cost | (Q/2) * H = | 495 | ||||||
| Annual ordering cost | (D/Q) * S = | 494.9494949495 | ||||||
| Annual purchase cost | P * D = | 24500 | ||||||
| Total Annual Cost | TC = | 25489.9494949495 | ||||||
| 16. | Quantity Discounts | |||||||
| Price Level: | 1 | 2 | 3 | |||||
| A | Minimum quantity for price | Qmin = | 1 | 200 | 500 | |||
| Price | P = | 14.00 | 13.80 | 13.60 | ||||
| Optimal Q (for each price) | Qopt = | 468 | 472 | 500 | ||||
| Number of orders per year | D/Qopt = | 20.5128205128 | 20.3389830508 | 19.2 | ||||
| Average Inventory | Qopt/2 = | 234 | 236 | 250 | ||||
| Annual carrying cost | (Qopt/2) * H = | 819 | 814.2 | 850 | ||||
| Annual ordering cost | (D/Qopt) * S = | 820.5128205128 | 813.5593220339 | 768 | ||||
| Annual purchase cost | P * D = | 134400 | 132480 | 130560 | ||||
| Total Annual Cost | TC = | 136039.512820513 | 134107.759322034 | 132178 | ||||
| Annual Demand | D = | 9600 | ||||||
| Ordering cost per order | S = | 40 | ||||||
| Annual carrying cost per unit: | H (fixed) = | |||||||
| 2 | FALSE | H (% of price) = | 25.00% | |||||
| Optimal Q (overall) | Qopt = | 500 | ||||||
| Actual Order Quantity | Q = | 500 | ||||||
| Increment | DQ = | 10 | ||||||
| Price | P = | 13.6 | ||||||
| Number of orders per year | D/Q = | 19.2 | ||||||
| Average Inventory | Q/2 = | 250 | ||||||
| Annual carrying cost | (Q/2) * H = | 850 | ||||||
| Annual ordering cost | (D/Q) * S = | 768 | ||||||
| Annual purchase cost | P * D = | 130560 | ||||||
| Total Annual Cost | TC = | 132178 | ||||||
| Quantity Discounts | ||||||||
| Price Level: | 1 | 2 | 3 | |||||
| B | Minimum quantity for price | Qmin = | 1 | 150 | 350 | |||
| Price | P = | 14.10 | 13.90 | 13.70 | ||||
| Optimal Q (for each price) | Qopt = | 467 | 470 | 474 | ||||
| Number of orders per year | D/Qopt = | 20.556745182 | 20.4255319149 | 20.253164557 | ||||
| Average Inventory | Qopt/2 = | 233.5 | 235 | 237 | ||||
| Annual carrying cost | (Qopt/2) * H = | 823.0875 | 816.625 | 811.725 | ||||
| Annual ordering cost | (D/Qopt) * S = | 822.2698072805 | 817.0212765957 | 810.1265822785 | ||||
| Annual purchase cost | P * D = | 135360 | 133440 | 131520 | ||||
| Total Annual Cost | TC = | 137005.357307281 | 135073.646276596 | 133141.851582278 | ||||
| Annual Demand | D = | 9600 | ||||||
| Ordering cost per order | S = | 40 | ||||||
| Annual carrying cost per unit: | H (fixed) = | |||||||
| 2 | FALSE | H (% of price) = | 25.00% | |||||
| Optimal Q (overall) | Qopt = | 474 | ||||||
| Actual Order Quantity | Q = | 474 | ||||||
| Increment | DQ = | 10 | ||||||
| Price | P = | 13.7 | ||||||
| Number of orders per year | D/Q = | 20.253164557 | ||||||
| Average Inventory | Q/2 = | 237 | ||||||
| Annual carrying cost | (Q/2) * H = | 811.725 | ||||||
| Annual ordering cost | (D/Q) * S = | 810.1265822785 | ||||||
| Annual purchase cost | P * D = | 131520 | ||||||
| Total Annual Cost | TC = | 133141.851582278 | ||||||
| 17. | Quantity Discounts | |||||||
| Price Level: | 1 | 2 | 3 | |||||
| Minimum quantity for price | Qmin = | 1 | 200 | 801 | ||||
| Price | P = | 1.20 | 1.10 | 1.00 | ||||
| Optimal Q (for each price) | Qopt = | 240 | 240 | 801 | ||||
| Number of orders per year | D/Qopt = | 15 | 15 | 4.4943820225 | ||||
| Average Inventory | Qopt/2 = | 120 | 120 | 400.5 | ||||
| Annual carrying cost | (Qopt/2) * H = | 1200 | 1200 | 4005 | ||||
| Annual ordering cost | (D/Qopt) * S = | 1200 | 1200 | 359.5505617978 | ||||
| Annual purchase cost | P * D = | 4320 | 3960 | 3600 | ||||
| Total Annual Cost | TC = | 6720 | 6360 | 7964.5505617977 | ||||
| Annual Demand | D = | 3600 | ||||||
| Ordering cost per order | S = | 80 | ||||||
| Annual carrying cost per unit: | H (fixed) = | 10 | ||||||
| 1 | TRUE | H (% of price) = | ||||||
| Optimal Q (overall) | Qopt = | 240 | ||||||
| Actual Order Quantity | Q = | 240 | ||||||
| Increment | DQ = | 10 | ||||||
| Price | P = | 1.1 | ||||||
| Number of orders per year | D/Q = | 15 | ||||||
| Average Inventory | Q/2 = | 120 | ||||||
| Annual carrying cost | (Q/2) * H = | 1200 | ||||||
| Annual ordering cost | (D/Q) * S = | 1200 | ||||||
| Annual purchase cost | P * D = | 3960 | ||||||
| Total Annual Cost | TC = | 6360 | ||||||
| Actual Order Quantity | Q = | 800 | ||||||
| Increment | DQ = | 10 | ||||||
| Price | P = | 1.1 | ||||||
| Number of orders per year | D/Q = | 4.5 | ||||||
| Average Inventory | Q/2 = | 400 | ||||||
| Annual carrying cost | (Q/2) * H = | 4000 | ||||||
| Annual ordering cost | (D/Q) * S = | 360 | ||||||
| Annual purchase cost | P * D = | 3960 | ||||||
| Total Annual Cost | TC = | 8320 | ||||||
| 19. | Reorder Point (ROP) with EOQ Ordering | |||||||
| Average demand | d = | 300 | ||||||
| Std dev demand | sd = | 30 | ||||||
| Average lead time | LT = | 1 | ||||||
| Std dev lead time | sLT = | 0 | ||||||
| Service level | SL = | 0.99 | ||||||
| Increment | DSL = | 0.01 | ||||||
| Stock out risk | 0.01 | |||||||
| Average demand during lead time | dLT = | 300 | ||||||
| Std dev demand during lead tTime | sdLT = | 30 | ||||||
| Safety stock | SS = | 69.7902578395 | ||||||
| Reorder point | ROP = | 369.7902578395 | ||||||
| 20. | Reorder Point (ROP) with EOQ Ordering | |||||||
| Average demand | d = | 600 | ||||||
| Std dev demand | sd = | 52 | ||||||
| Average lead time | LT = | 1 | ||||||
| Std dev lead time | sLT = | 0 | ||||||
| Service level | SL = | 0.96 | ||||||
| Increment | DSL = | 0.01 | ||||||
| Stock out risk | 0.04 | |||||||
| Average demand during lead time | dLT = | 600 | ||||||
| Std dev demand during lead tTime | sdLT = | 52 | ||||||
| Safety stock | SS = | 91.035690275 | ||||||
| Reorder point | ROP = | 691.035690275 | ||||||
| 20c. | Reorder Point (ROP) with EOQ Ordering | |||||||
| Average demand | d = | 600 | ||||||
| Std dev demand | sd = | 52 | ||||||
| Average lead time | LT = | 1 | ||||||
| Std dev lead time | sLT = | 0 | ||||||
| Service level | SL = | 0.5 | ||||||
| Increment | DSL = | 0.01 | ||||||
| Stock out risk | 0.5 | |||||||
| Average demand during lead time | dLT = | 600 | ||||||
| Std dev demand during lead time | sdLT = | 52 | ||||||
| z = | -1.39213763529183E-16 | |||||||
| Safety stock | SS = | -0 | ||||||
| Reorder point | ROP = | 600 |
Problems 21-28
| Chapter 13 - Problems 20-28 | Note: This worksheet displays results only, you must copy the shaded | ||||||
| <Back | area into the corresponding template to make additional calculations. | ||||||
| 21a. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 21 | |||||
| Std dev demand | sd = | 3.5 | |||||
| Average lead time | LT = | 0.2857142857 | |||||
| Std dev lead time | sLT = | 0 | |||||
| Service level | SL = | 0.9 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.1 | ||||||
| Average demand during lead time | dLT = | 6 | |||||
| Std dev demand during lead tTime | sdLT = | 1.8708286934 | |||||
| Safety stock | SS = | 2.3975619981 | |||||
| Reorder point | ROP = | 8.3975619981 | |||||
| ROP / d = | 0.3998839734 | week | |||||
| = | 2.7991878136 | days | |||||
| 21b. | Fixed Order Interval Model | ||||||
| Average demand | d = | 21 | |||||
| Std dev demand | sd = | 3.5 | |||||
| Lead time | LT = | 0.2857142857 | |||||
| Amount on hand at reorder time | A = | 8 | |||||
| Order interval | OI = | 1.4285714286 | |||||
| Service level | SL = | 0.9 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.1 | ||||||
| Average demand during lead time | dLT = | 36 | |||||
| Safety stock | SS = | 5.8728035222 | |||||
| Amount to order | 33.8728035222 | ||||||
| 22c. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 21 | |||||
| Std dev demand | sd = | 3.5 | |||||
| Average lead time | LT = | 0.2857142857 | |||||
| Std dev lead time | sLT = | 0 | |||||
| Service level | SL = | 0.5825670042 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.4174329958 | ||||||
| Average demand during lead time | dLT = | 6 | |||||
| Std dev demand during lead time | sdLT = | 1.8708286934 | |||||
| Safety stock | SS = | 0.3900028285 | |||||
| Reorder point | ROP = | 6.3900028285 | |||||
| Use goal seek to set ROP = 6.39 (2 gallons below previous ROP) by changing SL. | |||||||
| 22. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 30 | |||||
| Std dev demand | sd = | 18.6462195427 | |||||
| Average lead time | LT = | 4 | |||||
| Std dev lead time | sLT = | 0 | |||||
| Service level | SL = | 0.91 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.09 | ||||||
| Average demand during lead time | dLT = | 120 | |||||
| Std dev demand during lead tTime | sdLT = | 37.2924390855 | |||||
| Safety stock | SS = | 50 | |||||
| Reorder point | ROP = | 170 | |||||
| Average demand | d = | 30 | |||||
| Std dev demand | sd = | 18.6462195427 | |||||
| Average lead time | LT = | 4 | |||||
| Std dev lead time | sLT = | 0 | |||||
| Service level | SL = | 0.97 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.03 | ||||||
| Average demand during lead time | dLT = | 120 | |||||
| Std dev demand during lead tTime | sdLT = | 37.2924390855 | |||||
| Safety stock | SS = | 70.139230417 | |||||
| Reorder point | ROP = | 190.139230417 | |||||
| 23. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 85 | |||||
| Std dev demand | sd = | 0 | |||||
| Average lead time | LT = | 6 | |||||
| Std dev lead time | sLT = | 1.1 | |||||
| Service level | SL = | 0.8906409726 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.1093590274 | ||||||
| Average demand during lead time | dLT = | 510 | |||||
| Std dev demand during lead time | sdLT = | 93.5 | |||||
| Safety stock | SS = | 114.9997444827 | |||||
| Reorder point | ROP = | 624.9997444827 | |||||
| 24. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 12 | |||||
| Std dev demand | sd = | 2 | |||||
| Average lead time | LT = | 4 | |||||
| Std dev lead time | sLT = | 1 | |||||
| Service level | SL = | 0.96 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.04 | ||||||
| Average demand during lead time | dLT = | 48 | |||||
| Std dev demand during lead time | sdLT = | 12.6491106407 | |||||
| Safety stock | SS = | 22.1446253565 | |||||
| Reorder point | ROP = | 70.1446253565 | |||||
| 25a. | Quantity Discounts | ||||||
| Price Level: | 1 | 2 | 3 | ||||
| Minimum quantity for price | Qmin = | 1 | 400 | 800 | |||
| Price | P = | 2.00 | 1.70 | 1.62 | |||
| Optimal Q (for each price) | Qopt = | 300 | 400 | 800 | |||
| Number of orders per year | D/Qopt = | 15 | 11.25 | 5.625 | |||
| Average Inventory | Qopt/2 = | 150 | 200 | 400 | |||
| Annual carrying cost | (Qopt/2) * H = | 450 | 600 | 1200 | |||
| Annual ordering cost | (D/Qopt) * S = | 450 | 337.5 | 168.75 | |||
| Annual purchase cost | P * D = | 9000 | 7650 | 7290 | |||
| Total Annual Cost | TC = | 9900 | 8587.5 | 8658.75 | |||
| Annual Demand | D = | 4500 | |||||
| Ordering cost per order | S = | 30 | |||||
| Annual carrying cost per unit: | H (fixed) = | 3 | |||||
| 1 | TRUE | H (% of price) = | |||||
| Optimal Q (overall) | Qopt = | 400 | |||||
| Actual Order Quantity | Q = | 800 | |||||
| Increment | DQ = | 10 | |||||
| Price | P = | 1.62 | |||||
| Number of orders per year | D/Q = | 5.625 | |||||
| Average Inventory | Q/2 = | 400 | |||||
| Annual carrying cost | (Q/2) * H = | 1200 | |||||
| Annual ordering cost | (D/Q) * S = | 168.75 | |||||
| Annual purchase cost | P * D = | 7290 | |||||
| Total Annual Cost | TC = | 8658.75 | |||||
| 25b. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 12.5 | |||||
| Std dev demand | sd = | 2 | |||||
| Average lead time | LT = | 3 | |||||
| Std dev lead time | sLT = | 0 | |||||
| Service level | SL = | 0.985 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.015 | ||||||
| Average demand during lead time | dLT = | 37.5 | |||||
| Std dev demand during lead time | sdLT = | 3.4641016151 | |||||
| Safety stock | SS = | 7.5174148313 | |||||
| Reorder point | ROP = | 45.0174148313 | |||||
| 26a. | Basic Economic Order Quantity (EOQ) Model | ||||||
| Annual Demand | D = | 260 | |||||
| Ordering cost per order | S = | 2 | |||||
| Annual carrying cost per unit | H = | 0.2 | |||||
| Working days per year | D/Y = | 360 | |||||
| Economic Order Quantity | EOQ = | 72.1110255093 | |||||
| 26b. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 5 | |||||
| Std dev demand | sd = | 0.5 | |||||
| Average lead time | LT = | 2 | |||||
| Std dev lead time | sLT = | 0 | |||||
| Service level | SL = | 0.9976694316 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.0023305684 | ||||||
| Average demand during lead time | dLT = | 10 | |||||
| Std dev demand during lead time | sdLT = | 0.7071067812 | |||||
| Safety stock | SS = | 2.0007919821 | |||||
| Reorder point | ROP = | 12.0007919821 | |||||
| 26c. | Fixed Order Interval Model | ||||||
| Average demand | d = | 5 | |||||
| Std dev demand | sd = | 0.5 | |||||
| Lead time | LT = | 2 | |||||
| Amount on hand at reorder time | A = | 12 | |||||
| Order interval | OI = | 7 | |||||
| Service level | SL = | 0.9772715419 | |||||
| Increment | DSL = | 0.01 | |||||
| Stock out risk | 0.0227284581 | ||||||
| Average demand during lead time | dLT = | 45 | |||||
| Safety stock | SS = | 3.0005958251 | |||||
| Amount to order | 36.0005958251 | ||||||
| 27. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 80 | |||||
| Std dev demand | sd = | 10 | |||||
| Average lead time | LT = | 8 | |||||
| Std dev lead time | sLT = | 1 | |||||
| Service level | SL = | 0.9 | |||||
| Increment | DSL = | 0.0001 | |||||
| Stock out risk | 0.1 | ||||||
| Average demand during lead time | dLT = | 640 | |||||
| Std dev demand during lead time | sdLT = | 84.8528137424 | |||||
| Safety stock | SS = | 108.7431908564 | |||||
| Reorder point | ROP = | 748.7431908564 | |||||
| 28a. | Basic Economic Order Quantity (EOQ) Model | ||||||
| Annual Demand | D = | 3600 | |||||
| Ordering cost per order | S = | 1 | |||||
| Annual carrying cost per unit | H = | 0.4 | |||||
| Working days per year | D/Y = | 360 | |||||
| Economic Order Quantity | EOQ = | 134.16407865 | |||||
| 28b. | Reorder Point (ROP) with EOQ Ordering | ||||||
| Average demand | d = | 10 | |||||
| Std dev demand | sd = | 2 | |||||
| Average lead time | LT = | 3 | |||||
| Std dev lead time | sLT = | 0 | |||||
| Service level | SL = | 0.96 | |||||
| Increment | DSL = | 0.0001 | |||||
| Stock out risk | 0.04 | ||||||
| Average demand during lead time | dLT = | 30 | |||||
| Std dev demand during lead time | sdLT = | 3.4641016151 | |||||
| Safety stock | SS = | 6.0645554176 | |||||
| Reorder point | ROP = | 36.0645554176 | |||||
Problems 31-39
| Chapter 13 - Problems 31-39 | Note: This worksheet displays results only, you must copy the shaded | |||||||
| <Back | area into the corresponding template to make additional calculations. | |||||||
| 31. | Fixed Order Interval Model | |||||||
| Average demand | d = | 40 | 40 | 40 | ||||
| Std dev demand | sd = | 3 | 3 | 3 | ||||
| Lead time | LT = | 2 | 2 | 2 | ||||
| Amount on hand at reorder time | A = | 42 | 8 | 103 | ||||
| Order interval | OI = | 14 | 14 | 14 | ||||
| Service level | SL = | 0.98 | 0.98 | 0.98 | ||||
| Increment | DSL = | 0.01 | 0.01 | 0.01 | ||||
| Stock out risk | 0.02 | 0.02 | 0.02 | |||||
| Average demand during lead time | dLT = | 640 | 640 | 640 | ||||
| Safety stock | SS = | 24.6449869276 | 24.6449869276 | 24.6449869276 | ||||
| Amount to order | 622.6449869276 | 656.6449869276 | 561.6449869276 | |||||
| 32a. | Average demand | d = | 60 | |||||
| Std dev demand | sd = | 4 | ||||||
| Average lead time | LT = | 2 | ||||||
| Std dev lead time | sLT = | 0 | ||||||
| Service level | SL = | 0.975 | ||||||
| Increment | DSL = | 0.0001 | ||||||
| Stock out risk | 0.025 | |||||||
| Average demand during lead time | dLT = | 120 | ||||||
| Std dev demand during lead time | sdLT = | 5.6568542495 | ||||||
| Safety stock | SS = | 11.0872141774 | ||||||
| Reorder point | ROP = | 131.0872141774 | ||||||
| 32b. | Basic Economic Order Quantity (EOQ) Model | |||||||
| Annual Demand | D = | 3000 | ||||||
| Ordering cost per order | S = | 70 | ||||||
| Annual carrying cost per unit | H = | 4.5 | ||||||
| Working days per year | D/Y = | 360 | ||||||
| Economic Order Quantity | EOQ = | 305.5050463304 | ||||||
| 32c. | Fixed Order Interval Model | |||||||
| Average demand | d = | 70 | ||||||
| Std dev demand | sd = | 5 | ||||||
| Lead time | LT = | 2 | ||||||
| Amount on hand at reorder time | A = | 110 | ||||||
| Order interval | OI = | 4 | ||||||
| Service level | SL = | 0.975 | ||||||
| Increment | DSL = | 0.01 | ||||||
| Stock out risk | 0.025 | |||||||
| Average demand during lead time | dLT = | 420 | ||||||
| Safety stock | SS = | 24.004522837 | ||||||
| Amount to order | 334.004522837 | |||||||
| 33a. | ABC Classification Syatem | |||||||
| Dollar Amount | Annual Demand | |||||||
| Class | Total | Percent | Total | Percent | ||||
| A | 2,745,000 | 72.50% | 66,000 | 31.44% | ||||
| B | 715,700 | 18.90% | 86,300 | 41.11% | ||||
| C | 325,650 | 8.60% | 57,650 | 27.46% | ||||
| Enter lower limit for dollar amount: | ||||||||
| A | 945,000 | B | 195,600 | |||||
| Unit | Dollar | |||||||
| Item | Usage | Cost | Amount | Class | ||||
| H4-010 | 20,000 | 2.50 | 50,000 | C | ||||
| H5-201 | 60,200 | 4.00 | 240,800 | B | ||||
| P6-400 | 9,800 | 28.50 | 279,300 | B | ||||
| P6-401 | 16,300 | 12.00 | 195,600 | B | ||||
| P7-100 | 6,250 | 9.00 | 56,250 | C | ||||
| P9-103 | 4,500 | 22.00 | 99,000 | C | ||||
| TS-300 | 21,000 | 45.00 | 945,000 | A | ||||
| TS-400 | 45,000 | 40.00 | 1,800,000 | A | ||||
| TS-041 | 800 | 20.00 | 16,000 | C | ||||
| V1-001 | 26,100 | 4.00 | 104,400 | C | ||||
| 34. | Single Period Model | |||||||
| Select demand distribution: | Discrete | |||||||
| 4 | ||||||||
| Shortage cost (revenue - cost) | Cs = | 1.6 | ||||||
| Excess cost (cost - salvage) | Ce = | 0.8 | ||||||
| Optimal Service Level | SLo = | 0.6666666667 | ||||||
| So = | ||||||||
| Adjust S until SL >= SLo | ||||||||
| Actual Stocking Level | S = | 25 | ||||||
| Increment | DS = | 1 | ||||||
| Actual Service Level | SL = | 0.7300 | ||||||
| Balance: | ||||||||
| Ce * Service Level | 0.584 | |||||||
| Cs * (1 - Service Level) | 0.432 | |||||||
| Discrete Distribution: | Demand | Freq | Cum | |||||
| 19 | 0.01 | 0.01 | ||||||
| 20 | 0.05 | 0.06 | ||||||
| 21 | 0.12 | 0.18 | ||||||
| 22 | 0.18 | 0.36 | ||||||
| 23 | 0.13 | 0.49 | ||||||
| 24 | 0.14 | 0.63 | ||||||
| 25 | 0.1 | 0.73 | ||||||
| 26 | 0.11 | 0.84 | ||||||
| 27 | 0.1 | 0.94 | ||||||
| 28 | 0.04 | 0.98 | ||||||
| 29 | 0.02 | 1 | ||||||
| 35a. | Single Period Model | |||||||
| Select demand distribution: | Poisson | |||||||
| FALSE | FALSE | TRUE | ||||||
| Shortage cost (revenue - cost) | Cs = | 88000 | ||||||
| Excess cost (cost - salvage) | Ce = | 245 | ||||||
| Average demand | 3.2 | |||||||
| Optimal Service Level | SLo = | 0.9972236387 | ||||||
| So = | ||||||||
| Adjust S until SL >= SLo | ||||||||
| Actual Stocking Level | S = | 9 | ||||||
| Increment | DS = | 1 | ||||||
| Actual Service Level | SL = | 0.9982 | ||||||
| Balance: | ||||||||
| Ce * Service Level | 244.5683374723 | |||||||
| Cs * (1 - Service Level) | 155.0461323991 | |||||||
| 35b. | Single Period Model | |||||||
| Select demand distribution: | Poisson | |||||||
| FALSE | FALSE | TRUE | ||||||
| Shortage cost (revenue - cost) | Cs = | 10.5203646911 | ||||||
| Excess cost (cost - salvage) | Ce = | 245 | ||||||
| Average demand | 3.2 | |||||||
| Optimal Service Level | SLo = | 0.041172314 | ||||||
| So = | ||||||||
| Adjust S until SL >= SLo | ||||||||
| Actual Stocking Level | S = | 0 | ||||||
| Increment | DS = | 1 | ||||||
| Actual Service Level | SL = | 0.0408 | ||||||
| Balance: | ||||||||
| Ce * Service Level | 9.9867399747 | |||||||
| Cs * (1 - Service Level) | 10.0915314396 | |||||||
| Set Actual Stocking Level to 0 to determine Actual Service Level (.0408). | ||||||||
| Then use goal seek to set Optimal Service Level tp .0408 by changing Cs. | ||||||||
| 36. | Single Period Model | |||||||
| Select demand distribution: | Normal | |||||||
| FALSE | TRUE | FALSE | ||||||
| Shortage cost (revenue - cost) | Cs = | 0.5 | ||||||
| Excess cost (cost - salvage) | Ce = | 0.6 | ||||||
| Average demand | 80 | |||||||
| Std dev demand | 10 | |||||||
| Optimal Service Level | SLo = | 0.4545454545 | ||||||
| Optimal Stocking Level | So = | 78.8581521393 | ||||||
| Actual Stocking Level | S = | 78.8581521393 | ||||||
| Increment | DS = | 1 | ||||||
| Actual Service Level | SL = | 0.4545 | ||||||
| Balance: | ||||||||
| Ce * Service Level | 0.2727273644 | |||||||
| Cs * (1 - Service Level) | 0.2727271963 | |||||||
| 37. | Single Period Model | |||||||
| Select demand distribution: | Normal | |||||||
| FALSE | TRUE | FALSE | ||||||
| Shortage cost (revenue - cost) | Cs = | 4.8889581632 | ||||||
| Excess cost (cost - salvage) | Ce = | 0.35 | ||||||
| Average demand | 40 | |||||||
| Std dev demand | 6 | |||||||
| Optimal Service Level | SLo = | 0.933192824 | ||||||
| Optimal Stocking Level | So = | 49.0000139608 | ||||||
| note: use Goal Seek to set So to 49 by changing Cs | ||||||||
| 38. | Single Period Model | |||||||
| Select demand distribution: | Poisson | |||||||
| Shortage cost (revenue - cost) | Cs = | 1 | ||||||
| Excess cost (cost - salvage) | Ce = | 1.5 | ||||||
| Average demand | 6 | |||||||
| Optimal Service Level | SLo = | 0.4 | ||||||
| So = | ||||||||
| Adjust S until SL >= SLo | ||||||||
| Actual Stocking Level | S = | 5 | ||||||
| Increment | DS = | 1 | ||||||
| Actual Service Level | SL = | 0.4457 | ||||||
| Balance: | ||||||||
| Ce * Service Level | 0.668519462 | |||||||
| Cs * (1 - Service Level) | 0.5543203586 | |||||||
| 39. | Single Period Model | |||||||
| Select demand distribution: | Normal | |||||||
| Shortage cost (revenue - cost) | Cs = | 0.4 | ||||||
| Excess cost (cost - salvage) | Ce = | 0.2 | ||||||
| Average demand | 400 | |||||||
| Std dev demand | 50 | |||||||
| Optimal Service Level | SLo = | 0.6666666667 | ||||||
| Optimal Stocking Level | So = | 421.5363797906 | ||||||
| Actual Stocking Level | S = | 421.5363797906 | ||||||
| Increment | DS = | 1 | ||||||
| Actual Service Level | SL = | 0.6667 | ||||||
| Balance: | ||||||||
| Ce * Service Level | 0.1333333487 | |||||||
| Cs * (1 - Service Level) | 0.1333333025 | |||||||
Problems 40-44
| Chapter 13 - Problems 40-44 | Note: This worksheet displays results only, you must copy the shaded | |||||
| <Back | area into the corresponding template to make additional calculations. | |||||
| 40a. | Single Period Model | |||||
| Select demand distribution: | Discrete | |||||
| 4 | ||||||
| Shortage cost (revenue - cost) | Cs = | 10 | 10 | |||
| Excess cost (cost - salvage) | Ce = | 0.5177605 | 1.7607217053 | |||
| Optimal Service Level | SLo = | 0.9507727429 | 0.8502879543 | |||
| So = | ||||||
| Adjust S until SL >= SLo | ||||||
| Actual Stocking Level | S = | 4 | 3 | |||
| Increment | DS = | 1 | 1 | |||
| Actual Service Level | SL = | 0.9500 | 0.8500 | |||
| Balance: | ||||||
| Ce * Service Level | 0.491872475 | 1.4966134495 | ||||
| Cs * (1 - Service Level) | 0.5 | 1.5 | ||||
| Discrete Distribution: | Demand | Freq | Cum | |||
| 0 | 0.3 | 0.3 | ||||
| 1 | 0.2 | 0.5 | ||||
| 2 | 0.2 | 0.7 | ||||
| 3 | 0.15 | 0.85 | ||||
| 4 | 0.1 | 0.95 | ||||
| 5 | 0.05 | 1 | ||||
| Since SL(4) = .95 and SL(3) = .85, use goal seek to set SLo to these values by changing Ce. | ||||||
| 40b. | Single Period Model | |||||
| Select demand distribution: | Discrete | |||||
| Shortage cost (revenue - cost) | Cs = | 189.0778609732 | 56.722521585 | |||
| Excess cost (cost - salvage) | Ce = | 10 | 10 | |||
| Optimal Service Level | SLo = | 0.9497683974 | 0.8501255684 | |||
| So = | ||||||
| Adjust S until SL >= SLo | ||||||
| Actual Stocking Level | S = | 4 | 3 | |||
| Increment | DS = | 1 | 1 | |||
| Actual Service Level | SL = | 0.9500 | 0.8500 | |||
| Balance: | ||||||
| Ce * Service Level | 9.5 | 8.5 | ||||
| Cs * (1 - Service Level) | 9.4538930487 | 8.5083782377 | ||||
| Since SL(4) = .95 and SL(3) = .85, use goal seek to set SLo to these values by changing Cs. | ||||||
| 41. | Single Period Model | |||||
| Select demand distribution: | Discrete | |||||
| 4 | ||||||
| Shortage cost (revenue - cost) | Cs = | 1000 | ||||
| Excess cost (cost - salvage) | Ce = | 150 | ||||
| Optimal Service Level | SLo = | 0.8695652174 | ||||
| So = | ||||||
| Adjust S until SL >= SLo | ||||||
| Actual Stocking Level | S = | 3 | ||||
| Increment | DS = | 1 | ||||
| Actual Service Level | SL = | 1.0000 | ||||
| Balance: | ||||||
| Ce * Service Level | 150 | |||||
| Cs * (1 - Service Level) | 0 | |||||
| Discrete Distribution: | Demand | Freq | Cum | |||
| 0 | 0.1 | 0.1 | ||||
| 1 | 0.5 | 0.6 | ||||
| 2 | 0.25 | 0.85 | ||||
| 3 | 0.15 | 1 | ||||
| Since SL(2) = .85 and SL(3) = 1.0, stock 3 spares. | ||||||
| 42b. | Single Period Model | |||||
| Select demand distribution: | Discrete | |||||
| 4 | ||||||
| Shortage cost (revenue - cost) | Cs = | 27 | ||||
| Excess cost (cost - salvage) | Ce = | 23 | ||||
| Optimal Service Level | SLo = | 0.54 | ||||
| So = | ||||||
| Adjust S until SL >= SLo | ||||||
| Actual Stocking Level | S = | 2 | ||||
| Increment | DS = | 1 | ||||
| Actual Service Level | SL = | 0.8000 | ||||
| Balance: | ||||||
| Ce * Service Level | 18.4 | |||||
| Cs * (1 - Service Level) | 5.4 | |||||
| Discrete Distribution: | Demand | Freq | Cum | |||
| 0 | 0.15 | 0.15 | ||||
| 1 | 0.35 | 0.5 | ||||
| 2 | 0.3 | 0.8 | ||||
| 3 | 0.2 | 1 | ||||
| Since SL(1) = .5 and SL(2) = .8, stock 2 cakes. | ||||||
| 43. | Single Period Model | |||||
| Select demand distribution: | Normal | |||||
| Shortage cost (revenue - cost) | Cs = | 99 | ||||
| Excess cost (cost - salvage) | Ce = | 200 | ||||
| Average demand | 18 | |||||
| Std dev demand | 4.55 | |||||
| Optimal Service Level | SLo = | 0.3311036789 | ||||
| Optimal Stocking Level | So = | 16.0122523416 | ||||
| Actual Stocking Level | S = | 16.0122523416 | ||||
| Increment | DS = | 1 | ||||
| Actual Service Level | SL = | 0.3311 | ||||
| Balance: | ||||||
| Ce * Service Level | 66.220735786 | |||||
| Cs * (1 - Service Level) | 66.220735786 | |||||
| 44. | Reorder Point (ROP) with EOQ Ordering | |||||
| Average demand | d = | 4.6 | ||||
| Std dev demand | sd = | 1.265 | ||||
| Average lead time | LT = | 3 | ||||
| Std dev lead time | sLT = | 0 | ||||
| Service level | SL = | 0.9723802611 | ||||
| Increment | DSL = | 0.01 | ||||
| Stock out risk | 0.0276197389 | |||||
| Average demand during lead time | dLT = | 13.8 | ||||
| Std dev demand during lead time | sdLT = | 2.1910442716 | ||||
| z = | 1.9169878295 | |||||
| Safety stock | SS = | 4.2002052026 | ||||
| Reorder point | ROP = | 18.0002052026 | ||||
| Use Goal Seek to set ROP = 18 |
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