MAt 540
Lecture notes
| WEEK 8 - LINEAR PROGRAMMING CONTINUED - APPLICATIONS | |||||||||||||||
| IN THIS CHAPTER, VARIOUS APPLICATIONS OF THE USE OF LINEAR PROGRAMMING | |||||||||||||||
| ARE ILLUSTRATED. WE WILL DISCUSS FIVE OF THESE EXAMPLES. | |||||||||||||||
| I. PRODUCT MIX - PAGE 111 - 116 | |||||||||||||||
| PROCESS. | COST | PROFIT | |||||||||||||
| PRODUCTS | TIME (HR.) | PER | PER | ||||||||||||
| TO BE MIXED | VARIABLE | PER DOZEN | DOZEN | DOZEN | |||||||||||
| Sweatshirt - Front | X1 | 0.10 | 36 | 90 | |||||||||||
| Sweatshirt - Both | X2 | 0.25 | 48 | 125 | |||||||||||
| T-Shirt - Front | X3 | 0.08 | 23 | 45 | |||||||||||
| T-Shirt - Both | X4 | 0.21 | 35 | 65 | |||||||||||
| OBJECTIVE - MAXIMIZE PROFITS | |||||||||||||||
| CONSTRAINTS | |||||||||||||||
| 1) PROCESSING TIME - MAXIMUM OF 72 HOURS | |||||||||||||||
| 2) SHIPPING CAPACITY - MAXIMUM OF 1,200 BOXES | |||||||||||||||
| [a sweatshirt is 3 times the size of a t-shirt] | |||||||||||||||
| 3) COST BUDGET - MAXIMUM OF $25,000 | |||||||||||||||
| 4) SWEATSHIRTS - MAXIMUM OF 500 DOZENS | |||||||||||||||
| 5) T-SHIRTS - MAXIMUM OF 500 DOZENS | |||||||||||||||
| THE LINEAR PROGRAMMING FORMULATION IS AS FOLLOWS: | |||||||||||||||
| QM FOR WINDOWS SOLUTION | |||||||||||||||
| INITIAL SCREEN | |||||||||||||||
| X1 | X2 | X3 | X4 | RHS | Equation form | ||||||||||
| Maximize | 90.0 | 125.0 | 45.0 | 65.0 | Max 90X1 + 125X2 + 45X3 + 65X4 | ||||||||||
| Constraint 1 | 0.1 | 0.25 | 0.08 | 0.21 | <= | 72 | .1X1 + .25X2 + .08X3 + .21X4 <= 72 | ||||||||
| Constraint 2 | 3 | 3 | 1 | 1 | <= | 1200 | 3X1 + 3X2 + X3 + X4 <= 1200 | ||||||||
| Constraint 3 | 36 | 48 | 25 | 35 | <= | 25000 | 36X1 + 48X2 + 25X3 + 35X4 <= 25000 | ||||||||
| Constraint 4 | 1 | 1 | 0 | 0 | <= | 500 | X1 + X2 <= 500 | ||||||||
| Constraint 5 | 0 | 0 | 1 | 1 | <= | 500 | X3 + X4 <= 500 | ||||||||
| FINAL SOLUTION SCREEN | |||||||||||||||
| Variable | Status | Value | |||||||||||||
| X1 | Basic | 175.5556 | 176 | ||||||||||||
| X2 | Basic | 57.7778 | 58 | ||||||||||||
| X3 | Basic | 500 | 234 | ||||||||||||
| X4 | NONBasic | 0 | |||||||||||||
| slack 1 | NONBasic | 0 | |||||||||||||
| slack 2 | NONBasic | 0 | |||||||||||||
| slack 3 | Basic | 3406.667 | |||||||||||||
| slack 4 | Basic | 266.6667 | |||||||||||||
| slack 5 | NONBasic | 0 | |||||||||||||
| Optimal Value (Z) | 45522.22 | ||||||||||||||
| 2. DIET PROBLEM PAGE 116 - 119 - TABLE OF DATA ON PAGE 116 | |||||||||||||||
| OBJECTIVE - MINIMIZE COSTS | |||||||||||||||
| CONSTRAINTS | |||||||||||||||
| 1) CALORIES - AT LEAST 420 CALORIES | |||||||||||||||
| 2) IRON - AT LEAST 5 MILLIGRAMS | |||||||||||||||
| 3) CALCIUM - AT LEAST 400 MILLIGRAMS | |||||||||||||||
| 4) PROTEIN - AT LEAST 20 GRAMS | |||||||||||||||
| 5) FIBER - AT LEAST 12 GRAMS | |||||||||||||||
| 6) FAT - MAXIMUM OF 20 GRAMS | |||||||||||||||
| 7) CHOLESTEROL - MAXIMUM OF 30 MILLIGRAMS | |||||||||||||||
| THE LINEAR PROGRAMMING FORMULATION IS AS FOLLOWS: | |||||||||||||||
| Subject to: | |||||||||||||||
| QM FOR WINDOWS SOLUTION | |||||||||||||||
| INITIAL SCREEN | |||||||||||||||
| X1 | X2 | X3 | X4 | X5 | X6 | X7 | X8 | X9 | X10 | RHS | Equation form | ||||
| Minimize | 0.18 | 0.22 | 0.1 | 0.12 | 0.1 | 0.09 | 0.4 | 0.16 | 0.5 | 0.07 | Min .18X1 + .22X2 + .1X3 + .12X4 + .1X5 + .09X6 + .4X7 + .16X8 + .5X9 + .07X10 | ||||
| Constraint 1 | 90 | 110 | 100 | 90 | 75 | 35 | 65 | 100 | 120 | 65 | >= | 420 | 90X1 + 110X2 + 100X3 + 90X4 + 75X5 + 35X6 + 65X7 + 100X8 + 120X9 + 65X10 >= 420 | ||
| Constraint 2 | 6 | 4 | 2 | 3 | 1 | 0 | 1 | 0 | 0 | 1 | >= | 5 | 6X1 + 4X2 + 2X3 + 3X4 + X5 + X7 + X10 >= 5 | ||
| Constraint 3 | 20 | 48 | 12 | 8 | 30 | 0 | 52 | 250 | 3 | 26 | >= | 400 | 20X1 + 48X2 + 12X3 + 8X4 + 30X5 + 52X7 + 250X8 + 3X9 + 26X10 >= 400 | ||
| Constraint 4 | 3 | 4 | 5 | 6 | 7 | 2 | 1 | 9 | 1 | 3 | >= | 20 | 3X1 + 4X2 + 5X3 + 6X4 + 7X5 + 2X6 + X7 + 9X8 + X9 + 3X10 >= 20 | ||
| Constraint 5 | 5 | 2 | 3 | 4 | 0 | 0 | 1 | 0 | 0 | 3 | >= | 12 | 5X1 + 2X2 + 3X3 + 4X4 + X7 3X10 >= 12 | ||
| Constraint 6 | 0 | 2 | 2 | 2 | 5 | 3 | 0 | 4 | 0 | 1 | <= | 20 | 2X2 + 2X3 + 2X4 + 5X5 + 3X6 + 4X8 + X10 <= 20 | ||
| Constraint 7 | 0 | 0 | 0 | 0 | 270 | 8 | 0 | 12 | 0 | 0 | <= | 30 | 270X5 + 8X6 + 12X8 <= 30 | ||
| FINAL SOLUTION SCREEN | |||||||||||||||
| Variable | Status | Value | |||||||||||||
| X1 | NONBasic | 0 | |||||||||||||
| X2 | NONBasic | 0 | |||||||||||||
| X3 | Basic | 1.0246 | |||||||||||||
| X4 | NONBasic | 0 | |||||||||||||
| X5 | NONBasic | 0 | |||||||||||||
| X6 | NONBasic | 0 | |||||||||||||
| X7 | NONBasic | 0 | |||||||||||||
| X8 | Basic | 1.2414 | |||||||||||||
| X9 | NONBasic | 0 | |||||||||||||
| X10 | Basic | 2.9754 | |||||||||||||
| surplus 1 | NONBasic | 0 | |||||||||||||
| surplus 2 | Basic | 0.0246 | |||||||||||||
| surplus 3 | NONBasic | 0 | |||||||||||||
| surplus 4 | Basic | 5.2217 | |||||||||||||
| surplus 5 | NONBasic | 0 | |||||||||||||
| slack 6 | Basic | 10.0099 | |||||||||||||
| slack 7 | Basic | 15.1035 | |||||||||||||
| Optimal Value (Z) | 0.5094 | ||||||||||||||
| 3. INVESTMENT EXAMPLE | |||||||||||||||
| RETURN | |||||||||||||||
| INVESTMENT | FROM | ||||||||||||||
| OPTIONS | VARIABLE | INVESTMENT | |||||||||||||
| Municipal bonds | X1 | 0.085 | |||||||||||||
| Cert. of deposit | X2 | 0.050 | |||||||||||||
| Treasury bills | X3 | 0.065 | |||||||||||||
| Growth stock fund | X4 | 0.130 | |||||||||||||
| OBJECTIVE: MAXIMIZE TOTAL RETURN ON INVESTMENTS | |||||||||||||||
| CONSTRAINTS | |||||||||||||||
| 1. TOTAL INVESTMENT IN MUNICIPAL BONDS - MAXIMUM OF 20% OF $70,000 | |||||||||||||||
| 2. AMOUNT INVESTED IN C.D's - MAXIMUM = SUM OF OTHER 3 ALTERNATIVES | |||||||||||||||
| 3. TOTAL INVESTMENT IN TREASURY BILLS AND CD's - AT LEAST 30% OF $70,000 | |||||||||||||||
| 4. TOTAL INVESTMENT IN TREASURY BILLS AND CD's - AT LEAST 1.2 TIMES | |||||||||||||||
| THE INVESTMENT IN MUNICIPAL BONDS AND GROWTH STOCK FUNDS. | |||||||||||||||
| 5. TOTAL INVESTMENT = $70,000 | |||||||||||||||
| THE LINEAR PROGRAMMING FORMULATION IS AS FOLLOWS: | |||||||||||||||
| NOTE: THE FOURTH CONSTRAINT IS DETERMINED AS FOLLOWS: | |||||||||||||||
| QM FOR WINDOWS SOLUTION | |||||||||||||||
| INITIAL SCREEN | |||||||||||||||
| X1 | X2 | X3 | X4 | RHS | Equation form | ||||||||||
| Maximize | 0.085 | 0.05 | 0.065 | 0.13 | Max .085X1 + .05X2 + .065X3 + .13X4 | ||||||||||
| Constraint 1 | 1 | 0 | 0 | 0 | <= | 14000 | X1 <= 14000 | ||||||||
| Constraint 2 | 1 | 1 | -1 | -1 | <= | 0 | X1 - X2 - X3 - X4 <= 0 | ||||||||
| Constraint 3 | 0 | 1 | 1 | 0 | >= | 21000 | X2 + X3 >= 21000 | ||||||||
| Constraint 4 | -1.2 | 1 | 1 | -1.2 | >= | 0 | --1.2X1 + X2 + X3 --1.2X4 >= 0 | ||||||||
| Constraint 5 | 1 | 1 | 1 | 1 | = | 70000 | X1 + X2 + X3 + X4 = 70000 | ||||||||
| FINAL SOLUTION SCREEN | |||||||||||||||
| Variable | Status | Value | |||||||||||||
| X1 | NONBasic | 0 | |||||||||||||
| X2 | NONBasic | 0 | |||||||||||||
| X3 | Basic | 38181.82 | |||||||||||||
| X4 | Basic | 31818.18 | 38181.816 | ||||||||||||
| slack 1 | Basic | 14000 | 38181.816 | ||||||||||||
| slack 2 | Basic | 70000 | |||||||||||||
| surplus 3 | Basic | 17181.82 | |||||||||||||
| surplus 4 | NONBasic | 0 | |||||||||||||
| artfcl 5 | NONBasic | 0 | |||||||||||||
| Optimal Value (Z) | 6618.182 | ||||||||||||||
| 4. MEDIA EXAMPLE (MARKETING EXAMPLE) | |||||||||||||||
| MEDIA | AUDIENCE | ||||||||||||||
| OPTIONS | VARIABLE | EXPOSURE | COST | ||||||||||||
| Television Comm. | X1 | 20,000 | $ 15,000 | ||||||||||||
| Radio Comm. | X2 | 12,000 | 6,000 | ||||||||||||
| Newspaper Ads | X3 | 9,000 | 4,000 | ||||||||||||
| OBJECTIVE: MAXIMIZE AUDIENCE EXPOSURE | |||||||||||||||
| CONSTRAINTS | |||||||||||||||
| 1. BUDGET LIMIT - MAXIMUM OF $100,000 | |||||||||||||||
| 2. TV STATION AVAILABILITY - MAXIMUM OF 4 COMMERCIALS | |||||||||||||||
| 3. RADIO STATION AVAILABILITY - MAXIMUM OF 10 COMMERCIALS | |||||||||||||||
| 4. NEWSPAPER AVAILABILITY - MAXIMUM OF 7 ADS | |||||||||||||||
| 5. AD AGENCY TIME AVAILABILITY - MAXIMUM OF 15 COMMERCIALS OR ADS. | |||||||||||||||
| THE LINEAR PROGRAMMING FORMULATION IS AS FOLLOWS: | |||||||||||||||
| QM FOR WINDOWS SOLUTION | |||||||||||||||
| INITIAL SCREEN | |||||||||||||||
| X1 | X2 | X3 | RHS | Equation form | |||||||||||
| Maximize | 20000 | 12000 | 9000 | Max 20000X1 + 12000X2 + 9000X3 | |||||||||||
| Constraint 1 | 15000 | 6000 | 4000 | <= | 100000 | 15000X1 + 6000X2 + 4000X3 <= 100000 | |||||||||
| Constraint 2 | 1 | 0 | 0 | <= | 4 | X1 <= 4 | |||||||||
| Constraint 3 | 0 | 1 | 0 | <= | 10 | X2 <= 10 | |||||||||
| Constraint 4 | 0 | 0 | 1 | <= | 7 | X3 <= 7 | |||||||||
| Constraint 5 | 1 | 1 | 1 | <= | 15 | X1 + X2 + X3 <= 15 | |||||||||
| FINAL SOLUTION SCREEN | |||||||||||||||
| Variable | Status | Value | |||||||||||||
| X1 | Basic | 1.8182 | 40000 | 2 | 30000 | ||||||||||
| X2 | Basic | 10 | 120000 | 10 | 60000 | ||||||||||
| X3 | Basic | 3.1818 | 27000 | 3 | 12000 | ||||||||||
| slack 1 | NONBasic | 0 | 187000 | 102000 | |||||||||||
| slack 2 | Basic | 2.1818 | |||||||||||||
| slack 3 | NONBasic | 0 | |||||||||||||
| slack 4 | Basic | 3.8182 | |||||||||||||
| slack 5 | NONBasic | 0 | |||||||||||||
| Optimal Value (Z) | 185000 | ||||||||||||||
| 5. TRANSPORTATION EXAMPLE | |||||||||||||||
| TRANSPORTATION COSTS | |||||||||||||||
| DESTINATION | |||||||||||||||
| SOURCE | New york | Dallas | Detroit | TOTALS | |||||||||||
| Cincinnati | $ 16 | $ 18 | $ 11 | 300 | |||||||||||
| Atlanta | $ 14 | $ 12 | $ 13 | 200 | |||||||||||
| Pittsburgh | $ 13 | $ 15 | $ 17 | 200 | |||||||||||
| 700 | |||||||||||||||
| TOTALS | 150 | 250 | 200 | 600 | |||||||||||
| OBJECTIVE: MINIMIZE TOTAL COST OF TRANSPORTATION | |||||||||||||||
| CONSTRAINTS | |||||||||||||||
| 1. AVAILABILITY FROM CINCINNATI - MAXIMUM OF 300 | |||||||||||||||
| 2. AVAILABILITY FROM ATLANTA - MAXIMUM OF 200 | |||||||||||||||
| 3. AVAILABILITY FROM PITTSBURGH - MAXIMUM OF 200 | |||||||||||||||
| 4. REQUIREMENTS FOR NEW YORK = 150 | |||||||||||||||
| 5. REQUIREMENTS FOR DALLAS = 250 | |||||||||||||||
| 6. REQUIREMENTS FOR DETROIT = 200 | |||||||||||||||
| QM FOR WINDOWS SOLUTION - USING THE TRANSPORTATION MODEL INSTEAD OF THE | |||||||||||||||
| LINEAR PROGRAMMING MODEL | |||||||||||||||
| INITIAL SCREEN | |||||||||||||||
| New York | Dallas | Detroit | SUPPLY | ||||||||||||
| Cincinnati | 16 | 18 | 11 | 300 | |||||||||||
| Atlanta | 14 | 12 | 13 | 200 | |||||||||||
| Pittsburgh | 13 | 15 | 17 | 200 | |||||||||||
| DEMAND | 150 | 250 | 200 | ||||||||||||
| FINAL SOLUTION SCREEN | |||||||||||||||
| Optimal solution value = $7300 | New York | Dallas | Detroit | Dummy | |||||||||||
| Cincinnati | 200 | 100 | |||||||||||||
| Atlanta | 200 | ||||||||||||||
| Pittsburgh | 150 | 50 | 0 | ||||||||||||
| Optimal solution value = $7300 |
Problems
| PROBLEMS 1 - 4 PAGES 147 - 148 | |||||||||
| I. | REVISED PRODUCT MIX PROBLEM | ||||||||
| 1a) | PROCESS. | COST | PROFIT | ||||||
| PRODUCTS | TIME (HR.) | PER | PER | ||||||
| TO BE MIXED | VARIABLE | PER DOZEN | DOZEN | DOZEN | |||||
| Sweatshirt - Front | X1 | 0.090 | 39.60 | 86.40 | |||||
| Sweatshirt - Both | X2 | 0.225 | 52.80 | 120.20 | |||||
| T-Shirt - Front | X3 | 0.072 | 25.30 | 42.70 | |||||
| T-Shirt - Both | X4 | 0.189 | 38.50 | 61.50 | |||||
| INITIAL SCREEN | |||||||||
| X1 | X2 | X3 | X4 | RHS | Equation form | ||||
| Maximize | 86.4 | 120.2 | 42.7 | 61.5 | Max 86.4X1 + 120.2X2 + 42.7X3 + 61.5X4 | ||||
| Constraint 1 | 0.09 | 0.225 | 0.072 | 0.189 | <= | 72 | .09X1 + .225X2 + .072X3 + .189X4 <= 72 | ||
| Constraint 2 | 3 | 3 | 1 | 1 | <= | 1200 | 3X1 + 3X2 + X3 + X4 <= 1200 | ||
| Constraint 3 | 36 | 48 | 25 | 35 | <= | 25000 | 36X1 + 48X2 + 25X3 + 35X4 <= 25000 | ||
| Constraint 4 | 1 | 1 | 0 | 0 | <= | 500 | X1 + X2 <= 500 | ||
| Constraint 5 | 0 | 0 | 1 | 1 | <= | 500 | X3 + X4 <= 500 | ||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | Basic | 122.2222 | |||||||
| X2 | Basic | 111.1111 | |||||||
| X3 | Basic | 500 | |||||||
| X4 | NONBasic | 0 | |||||||
| slack 1 | NONBasic | 0 | |||||||
| slack 2 | NONBasic | 0 | |||||||
| slack 3 | Basic | 2766.667 | |||||||
| slack 4 | Basic | 266.6667 | |||||||
| slack 5 | NONBasic | 0 | |||||||
| Optimal Value (Z) | 45265.55 | ||||||||
| THIS VALUE IS LOWER THAN THE ORIGINAL | |||||||||
| 1b) | TO MAKE ALL QUANTITIES EQUAL WE NEED TO ADD THE FOLLOWING | ||||||||
| CONSTRAINTS: | |||||||||
| 6: X1 = X2 or X1 - X2 = 0 | |||||||||
| 7: X1 = X3 or X1 - X3 = 0 | |||||||||
| 8: X1 = X4 or X1 - X4 = 0 | |||||||||
| INITIAL SCREEN | |||||||||
| X1 | X2 | X3 | X4 | RHS | Equation form | ||||
| Maximize | 90 | 125 | 45 | 65 | Max 90X1 + 125X2 + 45X3 + 65X4 | ||||
| Constraint 1 | 0.1 | 0.25 | 0.08 | 0.21 | <= | 72 | .1X1 + .25X2 + .08X3 + .21X4 <= 72 | ||
| Constraint 2 | 3 | 3 | 1 | 1 | <= | 1200 | 3X1 + 3X2 + X3 + X4 <= 1200 | ||
| Constraint 3 | 36 | 48 | 25 | 35 | <= | 25000 | 36X1 + 48X2 + 25X3 + 35X4 <= 25000 | ||
| Constraint 4 | 1 | 1 | 0 | 0 | <= | 500 | X1 + X2 <= 500 | ||
| Constraint 5 | 0 | 0 | 1 | 1 | <= | 500 | X3 + X4 <= 500 | ||
| NEW Constraint 6 | 1 | -1 | 0 | 0 | = | 0 | X1 - X2 = 0 | ||
| NEW Constraint 7 | 1 | 0 | -1 | 0 | = | 0 | X1 - X3 = 0 | ||
| NEW Constraint 8 | 1 | 0 | 0 | -1 | = | 0 | X1 - X4 = 0 | ||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | Basic | 112.5 | |||||||
| X2 | Basic | 112.5 | |||||||
| X3 | Basic | 112.5 | |||||||
| X4 | Basic | 112.5 | |||||||
| slack 1 | NONBasic | 0 | |||||||
| slack 2 | Basic | 300 | |||||||
| slack 3 | Basic | 8800 | |||||||
| slack 4 | Basic | 275 | |||||||
| slack 5 | Basic | 275 | |||||||
| artfcl 6 | NONBasic | 0 | |||||||
| artfcl 7 | NONBasic | 0 | |||||||
| artfcl 8 | NONBasic | 0 | |||||||
| Optimal Value (Z) | 36562.5 | ||||||||
| II. | REVISED DIET PROBLEM | ||||||||
| 2a | CHANGE THE MINIMUM CALORIE REQUIREMENT FOR THE BREAKFAST | ||||||||
| TO 500 CALORIES | |||||||||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | NONBasic | 0 | |||||||
| X2 | NONBasic | 0 | |||||||
| X3 | Basic | 2.9951 | |||||||
| X4 | NONBasic | 0 | |||||||
| X5 | NONBasic | 0 | |||||||
| X6 | NONBasic | 0 | |||||||
| X7 | NONBasic | 0 | |||||||
| X8 | Basic | 1.3517 | |||||||
| X9 | NONBasic | 0 | |||||||
| X10 | Basic | 1.0049 | |||||||
| surplus 1 | NONBasic | 0 | |||||||
| surplus 2 | Basic | 1.9951 | |||||||
| surplus 3 | NONBasic | 0 | |||||||
| surplus 4 | Basic | 10.1557 | |||||||
| surplus 5 | NONBasic | 0 | |||||||
| slack 6 | Basic | 7.598 | |||||||
| slack 7 | Basic | 13.7793 | |||||||
| Optimal Value (Z) | 0.5861 | ||||||||
| 2b | CHANGE THE MINIMUM CALORIE REQUIREMENT FOR THE BREAKFAST | ||||||||
| TO 600 CALORIES | |||||||||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | NONBasic | 0 | |||||||
| X2 | NONBasic | 0 | |||||||
| X3 | Basic | 4.6218 | |||||||
| X4 | NONBasic | 0 | |||||||
| X5 | NONBasic | 0 | |||||||
| X6 | NONBasic | 0 | |||||||
| X7 | NONBasic | 0 | |||||||
| X8 | Basic | 1.3782 | |||||||
| X9 | NONBasic | 0 | |||||||
| X10 | NONBasic | 0 | |||||||
| surplus 1 | NONBasic | 0 | |||||||
| surplus 2 | Basic | 4.2437 | |||||||
| surplus 3 | NONBasic | 0 | |||||||
| surplus 4 | Basic | 15.5126 | |||||||
| surplus 5 | Basic | 1.8655 | |||||||
| slack 6 | Basic | 5.2437 | |||||||
| slack 7 | Basic | 13.4622 | |||||||
| Optimal Value (Z) | 0.6827 | ||||||||
| 2c | CHANGE THE MINIMUM CALORIE REQUIREMENT FOR THE BREAKFAST | ||||||||
| TO 700 CALORIES | |||||||||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | NONBasic | 0 | |||||||
| X2 | NONBasic | 0 | |||||||
| X3 | Basic | 5.6723 | |||||||
| X4 | NONBasic | 0 | |||||||
| X5 | NONBasic | 0 | |||||||
| X6 | NONBasic | 0 | |||||||
| X7 | NONBasic | 0 | |||||||
| X8 | Basic | 1.3277 | |||||||
| X9 | NONBasic | 0 | |||||||
| X10 | NONBasic | 0 | |||||||
| surplus 1 | NONBasic | 0 | |||||||
| surplus 2 | Basic | 6.3445 | |||||||
| surplus 3 | NONBasic | 0 | |||||||
| surplus 4 | Basic | 20.3109 | |||||||
| surplus 5 | Basic | 5.0168 | |||||||
| slack 6 | Basic | 3.3445 | |||||||
| slack 7 | Basic | 14.0672 | |||||||
| Optimal Value (Z) | 0.7797 | ||||||||
| III. | REVISED INVESTMENT PROBLEM | ||||||||
| 3a | CHANGE THE $70,000 INVESTMENT AMOUNT FROM AN EQUALITY | ||||||||
| TO A MAXIMUM AMOUNT. | |||||||||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | NONBasic | 0 | |||||||
| X2 | NONBasic | 0 | |||||||
| X3 | Basic | 38181.82 | |||||||
| X4 | Basic | 31818.18 | |||||||
| slack 1 | Basic | 14000 | |||||||
| slack 2 | Basic | 70000 | |||||||
| surplus 3 | Basic | 17181.82 | |||||||
| surplus 4 | NONBasic | 0 | |||||||
| slack 5 | NONBasic | 0 | |||||||
| Optimal Value (Z) | 6618.182 | ||||||||
| THE CHANGE HAS NO EFFECT, SINCE THE ENTIRE $70,000 | |||||||||
| IS INVESTED ANYWAY. | |||||||||
| 3b | IF THE AMOUNT AVAILABLE IS INCREASED TO $80,000, | ||||||||
| WHAT WOULD BE THE NEW SOLUTION? | |||||||||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | NONBasic | 0 | |||||||
| X2 | NONBasic | 0 | |||||||
| X3 | Basic | 43636.36 | |||||||
| X4 | Basic | 36363.64 | 43636.368 | ||||||
| slack 1 | Basic | 14000 | |||||||
| slack 2 | Basic | 80000 | |||||||
| surplus 3 | Basic | 22636.37 | |||||||
| surplus 4 | NONBasic | 0 | |||||||
| slack 5 | NONBasic | 0 | |||||||
| Optimal Value (Z) | 7563.636 | ||||||||
| ALL $80,000 WILL BE INVESTED. | |||||||||
| THE OPTIMAL VALUE WILL INCREASE FROM | |||||||||
| $6,618.18 TO $7,563.64, AND INCREASE OF | 945.45 | ||||||||
| THE $10,000 INCREASE WILL BE SPLIT BETWEEN | |||||||||
| X3 AND X4. | |||||||||
| IV. | REVISED MARKETING PROBLEM | ||||||||
| 4a | INCREASE THE BUDGET BY $20,000. | ||||||||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | Basic | 3.6364 | |||||||
| X2 | Basic | 10 | |||||||
| X3 | Basic | 1.3636 | |||||||
| slack 1 | NONBasic | 0 | |||||||
| slack 2 | Basic | 0.3636 | |||||||
| slack 3 | NONBasic | 0 | |||||||
| slack 4 | Basic | 5.6364 | |||||||
| slack 5 | NONBasic | 0 | |||||||
| Optimal Value (Z) | 205000 | ||||||||
| THE OPTIMAL VALUE INCREASES BY 20,000, FROM 185,000 | |||||||||
| TO 205,000. | |||||||||
| 4b | IF THE STORE WANTS THE SAME NUMBER OF PEOPLE TO BE | ||||||||
| EXPOSED TO EACH TYPE OF ADVERTISMENT, WHAT CHANGES | |||||||||
| SHOULD BE MADE IN THE FORMULATION, AND WHAT WOULD BE | |||||||||
| THE NEW SOLUTION, ASSUMING THE NEW BUDGET REMAINS AT | |||||||||
| $120,000 | |||||||||
| TWO NEW CONSTRAINTS ARE NEEDED: | |||||||||
| 6) 20000X1 = 12000X2; OR 20000X1 - 12000X2 = 0 | |||||||||
| 7) 20000X1 = 9000X3; OR 20000X1 - 12000X3 = 0 | |||||||||
| FINAL SOLUTION SCREEN | |||||||||
| Variable | Status | Value | |||||||
| X1 | Basic | 3.0682 | |||||||
| X2 | Basic | 5.1136 | |||||||
| X3 | Basic | 6.8182 | |||||||
| slack 1 | Basic | 16022.73 | |||||||
| slack 2 | Basic | 0.9318 | |||||||
| slack 3 | Basic | 4.8864 | |||||||
| slack 4 | Basic | 0.1818 | |||||||
| slack 5 | NONBasic | 0 | |||||||
| artfcl 6 | NONBasic | 0 | |||||||
| artfcl 7 | NONBasic | 0 | |||||||
| Optimal Value (Z) | 184090.9 |
Key Points
| WEEK 8 - CHAPTER 4 - KEY POINTS TO REMEMBER | |
| 1 | When formulating a linear programming model on a spreadsheet, |
| the measure of performance is located in the target cell. | |
| 2 | Determining the production quantities of different products manufactured |
| by a company based on resource constraints is a product mix linear programming problem. | |
| 3 | When using linear programming model to solve the "diet" problem, |
| the objective is generally to minimize cost. | |
| 4 | The standard form for the computer solution of a linear programming problem requires |
| all variables to the left and all numerical values to the right of the inequality or equality sign. | |
| 5 | A constraint for a linear programming problem can have a zero as its right-hand-side value. |
| 6 | Media selection is an important decision that advertisers have to make. |
| In most media selection decisions, the objective of the decision maker is not to minimize cost. | |
| 7 | In a media selection problem, instead of having an objective of maximizing profit or |
| minimizing cost, generally the objective is to maximize the audience exposure. | |
| 8 | Linear programming model of a media selection problem is used to determine |
| the allocation of the advertising budget to various advertising media. | |
| 9 | In a balanced transportation model, supply equals demand such that all |
| constraints can be treated as equalities. | |
| 10 | In an unbalanced transportation model, supply does not equal demand |
| and supply constraints have signs. | |
| 11 | Feasible solutions are ones that satisfy all the constraints simultaneously. |
| 12 | In a media selection problem, the estimated number of customers reached by |
| a given media would generally be specified in the objective function. | |
| Even if these media exposure estimates are correct, using media exposure | |
| as a surrogate does not lead to maximization of profits. | |
| 13 | Profit is maximized in the objective function by subtracting costs from revenues. |
| 14 | In a multi-period scheduling problem the production constraint usually takes the form of : |
| beginning inventory - demand + production = ending inventory. |
Key Points 2
| WEEK 8 - CHAPTER 4 - KEY POINTS TO REMEMBER | ||
| 1 | The standard form for the computer solution of a linear programming problem | |
| requires all variables to the left and all numerical values to the right | ||
| of the inequality or equality sign. | ||
| 2 | Fractional relationships between variables are not permitted | |
| in the standard form of a linear program. | ||
| 3 | A constraint for a linear programming problem will sometimes | |
| have a zero as its right-hand-side value. | ||
| 4 | A systematic approach to model formulation does not require constructing | |
| the objective function before determining the decision variables | ||
| 5 | Product mix problems can have "greater than or equal to" (≥) constraints. | |
| 6 | When using linear programming model to solve the "diet" problem, | |
| the objective is generally to minimize cost. | ||
| 7 | In a balanced transportation model, supply equals demand such that | |
| all constraints can be treated as equalities. | ||
| 8 | In a transportation problem, a demand constraint (the amount of product | |
| demanded at a given destination) is an equal-to constraint (=). | ||
| 9 | In a media selection problem, instead of having an objective of maximizing | |
| profit or minimizing cost, generally the objective is to maximize | ||
| the audience exposure. | ||
| 10 | In formulating a typical diet problem using a linear programming model, we | |
| would not expect most of the constraints to be related to calories. | ||
| 11 | When systematically formulating a linear program, the first step is | |
| Identify the decision variables. | ||
| 12 | Compared to blending and product mix problems, transportation problems | |
| are unique because the solution values are always integers. | ||
| 13 | Balanced transportation problems have the equal (=) type of constraints. |
1234
1234
1234
1234
12
34
1234
:901254565
:
1)0.100.250.080.2172
2)331,200
3)3648253525,000
4)500
5)500
,,,0
MaximizeZxxxx
SubjectTo
xxxx
xxxx
xxxx
xx
xx
xxxx
=+++
+++£
+++£
+++£
+£
+£
³
123412341234123412341234:901254565:1)0.100.250.080.21722)331,2003)3648253525,0004)5005)500,,,0MaximizeZxxxxSubjectToxxxxxxxxxxxxxxxxxxxx
123456
:0.180.220.100.120.100.09
MinimizeZxxxxxx
=+++++
123456:0.180.220.100.120.100.09MinimizeZxxxxxx
78910
0.400.160.500.07
xxxx
++++
789100.400.160.500.07xxxx
12345678910
12345710
1234578910
12345678910
1234
1)901101009075356510012065420
2)64235
3)20481283052250326400
4)3456729320
5)5234
xxxxxxxxxx
xxxxxxx
xxxxxxxxx
xxxxxxxxxx
xxxx
+++++++++³
++++++³
++++++++³
+++++++++³
++++
710
23456810
568
312
6)22253420
7)27081230
0
i
xx
xxxxxxx
xxx
x
+³
++++++£
++£
³
123456789101234571012345789101234567891012341)9011010090753565100120654202)642353)204812830522503264004)34567293205)5234xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx710234568105683126)222534207)270812300ixxxxxxxxxxxxx
2314
2314
1234
1.2()
1.21.2
1.21.20
xxxx
xxxx
xxxx
+³+
+³+
-++-³
2314231412341.2()1.21.21.21.20xxxxxxxxxxxx
123
123
1
2
3
123
123
:20,00012,0009,000
:
1)15,0006,0004,000100,000
2)4
3)10
4)7
5)15
,,0
MaximizeZxxx
SubjectTo
xxx
x
x
x
xxx
xxx
=++
++£
£
£
£
++£
³
123123123123123:20,00012,0009,000:1)15,0006,0004,000100,0002)43)104)75)15,,0MaximizeZxxxSubjectToxxxxxxxxxxxx
1234
1
2134
2134
23
1234
1234
1234
:0.0850.0500.0650.130
:
1)14,000
2)
0
3)21,000
4)1.21.20
5)70,000
,,,0
MaximizeZxxxx
SubjectTo
x
xxxx
OR
xxxx
xx
xxxx
xxxx
xxxx
=+++
£
£++
---£
+³
-++-³
+++=
³
123412134213423123412341234:0.0850.0500.0650.130:1)14,0002)03)21,0004)1.21.205)70,000,,,0MaximizeZxxxxSubjectToxxxxxORxxxxxxxxxxxxxxxxxx