. An X chart is used to maintain current control of a process. The cost parame-

ters are 21 = $2, Q2 = $0.50,

a) = $50, aj = $75, and a= = $200. A single assignable cause occurs, with magni-

tude 5 = 1, and the run length of the process in control is exponentially dis-

tributed with mean 100 h. It requires 0.05 h to sample and test, and 1 h to locate the assignable cause.

(a) Evaluate the cost of the arbitrary ₮

chart design n = 5, k = 3, and h = 0.5.

(b) Find the economically optimum design.