1) C-Spec, Inc., is attempting to determine whether an existing machine is capable of milling an engine part that has a key specification of 4+6 .003 inches.

After a trial run on this machine, C-Spec has determined that the machine has a sample mean of 4.001 inches with a standard deviation of .002 inch.

a. Calculate the Cpk for this machine.

b. Should C-Spec use this machine to produce this part? Why?

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

Number of Number of Defective Items Defective Items Sample n in the Sample Sample n in the Sample

1                  15                                3                 6                             15                         2
2                  15                               1                 7                              15                         0
3                  15                               0                 8                              15                         3
4                   15                              0                 9                              15                         1
5                   15                              0                10                             15                         0

a. Develop a p-chart for 95 percent confi dence (1.96 standard deviation).

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