The thickness of a printed circuit board is an important quality parameter. Data on board thickness (in inches) are given in Table 6E.4 for 25 samples of three boards each.
(a) Set up and R control charts. Is the process in statistical control?
(b) Estimate the process standard deviation.
(c) What are the limits that you would expect to contain nearly all the process measurements?
(d) If the specifications are at 0.0630 in. ± 0.0015 in., what is the value of the PCR Cp?