17-4. Twenty-five samples of size 5 are drawn from a process at regular intervals, and the following data are obtained:
(a) Compute the control limits for the X and R charts.
(b) Assuming the process is in control and specification limits are 14.50 t 0.50, what conclusions can you draw about the ability of the process to operate within these limits? Estimate the percentage of defective items that will be produced.
(c) Calculate PCR and PCRK. Interpret these ratios.