Twenty samples with 100 units each were taken; with the following number of defectives in each respective sample: 8, 5, 3, 9, 4, 5, 8, 5, 3, 6, 4, 3, 5, 6, 2, 5, 0, 3, 4, and 2. Note: You may complete this problem using MS Excel and upload the spreadsheet as part of your submission or do it by hand and upload a scanned image or photo of your work.
a. Calculate the center line, upper control limit, and lower control limit for a 3s p-control chart. (Note: As your starting point, recall that p-charts represent percentages of defects for samples.)
b. Plot the points on the chart.
c. Comment on whether the process is stable enough to begin using these data for quality control purposes.