Operations Mgmt With Std Dvd Problem

Computer upgrades have a nominal time of 80 minutes. Samples of five observations each have been taken, and the results are as listed.

SAMPLE

123456

79.280.579.678.980.579.7

78.878.779.679.479.680.6

80.081.080.479.780.480.5

78.480.480.379.480.880.0

80.880.180.880.678.881.1

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Factors for three-sigma control limits for  and R charts

 FACTORS FOR R CHARTS

Number of Observations in Subgroup,

nFactor for

 Chart,

A2Lower

Control Limit,

D3Upper

Control Limit,

D4

2           1.88          03.27

3           1.02          02.57

4           0.73          02.28

5           0.58          02.11

6           0.48          02.00

7           0.42          0.081.92

8           0.37          0.141.86

9           0.34          0.181.82

10           0.31          0.221.78

11           0.29          0.261.74

12           0.27          0.281.72

13           0.25          0.311.69

14           0.24          0.331.67

15           0.22          0.351.65

16           0.21          0.361.64

17           0.20          0.381.62

18           0.19          0.391.61

19           0.19          0.401.60

20           0.18          0.411.59

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a.Using factors from above table, determine upper and lower control limits for mean and range charts.(Round your intermediate calculations and final answers to 2 decimal places. Leave no cells blank - be certain to enter "0" wherever required.)

            Mean Chart       Range Chart

  UCL 

  LCL 

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b.Decide if the process is in control.

Yes

No