Managing for Quality and Performance Excellence 9th Edition by James Evans,William Lindsay

Exercise 34

Note: Data for many of the problems in this chapter can be found in the Excel workbook C08Data.xlsx on the Student Companion Site. Click on the appropriate worksheet tab as noted in the problem (e.g., Prob. 8-6, etc.) to access the data.
The data for 30 samples of three items each, from the study at Birdseye Magnetronics (from Prob. 824, above), was further analyzed in an effort to use it for process control.
a. Compute the mean and range of each sample, calculate the control limits, and plot them on
and R control charts.
b. Does the process appear to be in statistical control? Why or why not?