To monitor the production of sheet metal screws by a machine in a large manufacturing company, a sample of 100 screws is examined each hour for three shifts of 8 hours each. Each screw is inspected and designated as conforming or nonconforming according to specifications. Management is willing to accept a proportion of nonconforming screws of 0.05. Use the following result of one day’s sampling (Table 2.13) to construct a control chart. Does the process seem to be in control? Explain.

Table 2.13 Data for Exercise 16 Sample ˆp Sample ˆp 1 0.04 13 0.09 2 0.07 14 0.10 3 0.05 15 0.09 4 0.03 16 0.11 5 0.04 17 0.10 6 0.06 18 0.12 7 0.05 19 0.13 8 0.03 20 0.09 9 0.05 21 0.14 10 0.07 22 0.11 11 0.09 23 0.15 12 0.10 24 0.16 LO.1