A manufacturer of component for automobile transmissions wants to use control charts to monitor a process producing a shaft. The resulting data from 20 samples of 4 shaft diameters that have been measured are:

(a) Find the control limits that should be
(b) Assume that the 20 preliminary samples plot in control on both charts. Estimate the process mean and standard deviation.

Transcribed Image Text:

20 20 ▽X= 10.275, yR= 1.012