What are the x overbar-chart control limits when the machine is working properly? Calculate the upper control limit of the x overbar-chart Calculate the lower control limit of the x overbar-chart. What are the R-chart control limits when the machine is working properly? Calculate the upper control limit of the R-chart. Calculate the lower control limit of the R-chart. The process is in control if all sample mean and range values are within the control limits. What seems to be happening? Has the process been in control? Yes or no?

What are the x overbar-chart control limits when the machine is working properly? Calculate the upper control limit of the x overbar-chart Calculate the lower control limit of the x overbar-chart. What are the R-chart control limits when the machine is working properly? Calculate the upper control limit of the R-chart. Calculate the lower control limit of the R-chart. The process is in control if all sample mean and range values are within the control limits. What seems to be happening? Has the process been in control? Yes or no?

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter13: Regression And Forecasting Models

Section13.7: Exponential Smoothing Models

Problem 28P: The file P13_28.xlsx contains monthly retail sales of U.S. liquor stores. a. Is seasonality present...

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Part 2

Set the control limits for this process for the

x-chart

when the machine is working properly.

a) What are the x overbar-chart control limits when the machine is working properly?

Calculate the upper control limit of the x overbar-chart

Calculate the lower control limit of the x overbar-chart.

What are the R-chart control limits when the machine is working properly?

Calculate the upper control limit of the R-chart.

Calculate the lower control limit of the R-chart.

The process is in control if all sample mean and range values are within the control limits. What seems to be happening? Has the process been in control? Yes or no?

Data Table
Sample
Size, n
2
3
4
5
6
7
8
9
10
12
Mean Factor,
A₂
1.880
1.023
0 729
0.577
0.483
0.419
0.373
0.337
0.308
0.266
Upper Range,
DA
3.268
2.574
2.282
2.115
2.004
1.924
1.864
1.816
1 777
1 716
A
Lower Range,
D3
0
0
0
0
0
0.076
0 136
0.184
0.223
0.284

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