Discussion:
The specifications call for a shaft to be 1.000 inch in diameter. The acceptable tolerances are +/- 0.005 inches. By doing a process study, you have determined that the average output of diameter is 1.002 and the standard deviation is 0.002. What is the probability that a shaft taken at random from the process will need to be reworked (is too large) or will need to be scrapped (is too small)? What then is the probability that a shaft will be acceptable? Assume that the diameter of the shaft is a random variable that is Normally distributed.