Question

A textbook publisher wants to determine process control charts for the textbook height. The following table shows the first 20 samples of n=4 sample size of the production of the text.

Sample - X Bar - Range
1 - 10.01 - .01
2 - 9.97 - .04
3 - 9.98 - .03
4 - 10.01 - .04
5 - 10.00 - .04
6 - 10.01 - .02
7 - 10.04 - .04
8 - 9.99 - .07
9 - 9.95 - .04
10 - 9.99 - .06
11 - 10.02 - .03
12 - 10.01 - .04
13 - 10.04 - .02
14 - 9.95 - .02
15 - 10.04 - .01
16 - 9.99 - .04
17 - 10.04 - .03
18 - 10.04 - .06
19 - 10.04 - .07
20 - 10.02 - .06

What are the upper and lower control limits for the X bar chart using the data from the samples above?

What are the upper and lower control limits for the R chart using the data from the samples above?

Discuss the charts you have plotted. What conclusions and recommendations do you make from those charts and the data?