During the morning hours at a catalog sales department, telephone calls come in at the rate (Poisson) of 32 per hour. Calls that cannot be answered immediately are put on hold. The system can handle 7 callers on hold. If additional calls come in, they receive a busy signal. The 3 customer service representatives who answer the calls spend an average of 5 minutes with a customer?.
a. What is the probability that a caller will get a busy signal?
b. What is the probability that a customer will be put on hold?