Defect monitoring. The following data are from a production process that makes 250 units each hour. The data were collected over a normal 12-hour shift one day. The data are shown in the table at the right.

Using the first 10 hours as the calibration period,

a) Calculate the center line of the p chart.

b) Calculate the upper control limit of the p chart.

c) Calculate the lower control limit of the p chart.

d) Create a p chart for the samples from the second set of 10 hours.

e) Is this process out of control?

Hour No. of Defects Sample Size 1 17 250 2 15 250 3 12 250 4 20 250 5 13 250 6 12 250 7 19 250 8 14 250 9 14 250 10 18 250 11 17 250 12 16 250 13 19 250 14 22 250 15 18 250 16 13 250 17 23 250 18 17 250 19 22 250 20 19 250