cudent rce Manual ts compre- e annotated ns to the mbered es included Answers to d Exercises in the this book. 6.1. A manufacturer of components 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: 20 20 Σ Ε = 10.275, Σ R = 1.012 i=1 i=1 (a) Find the control limits that should be used on the x and R control charts. (b) Assume that the 20 preliminary samples plot in control on both charts. Estimate the process mean and standard deviation.