Refer to Problem 17.22 on page 736 concerning waiting time for customers at a bank (data stored in BankTime). Suppose management has set a USL of five minutes on waiting time and specified that at least 99% of the waiting times must be less than five minutes in order for the process to be considered capable.
a. Estimate the percentage of the waiting times that are inside the specification limits. Is the process capable of meeting the company policy?
b. If management implemented a new policy, stating that 99.7% of all waiting times are required to be within specifications, is this process capable of reaching that goal? Explain.