1. A metal fabricator produces connecting rods with an outer diameter that has 1 +/- 0.01 cm specification. A machine operator takes several sample measurements over time and determines the sample mean outer diameter to be 1.002 cm with a standard deviation of 0.003 cm.

a. Calculate the process capability index for this sample.

b. What does this figure tell you about the process?

2. Ten samples of 15 parts each were taken from n ongoing process to establish a p=chart for control. The samples and the number of defectives in each are shown in the following table:

a. Develop a p-chart for 95% confidence (1.96 standard deviations).

b. Based on the plotted data points, what comments can you make?

NUMBER OF NUMBER OF DEFECTIVE ITEMS DEFECTIVE ITEMS SAMPLE n IN THE SAMPLE SAMPLE n IN THE SAMPLE 15720 3 15 7 15 UT A W N - 15 8 15 O - WON 15 OOO 15 15 10 15