Waiting time, relevant costs, and relevant revenues. The Orillia branch of Regal Bank is thinking of offering additional services to its customers. Its counter is open for five hours (300 minutes) each day (the operational capacity). If it introduces the new services, the bank expects to serve an average of 60 customers each day instead of the 42 customers it currently averages. It will take 4.5 minutes to serve each customer (service time) regardless of whether the new services are offered. (Note that the number of customers corresponds to the number of orders in the chapter discussion.)

Required 1. Using the formula on page 752, calculate how long, on average, a customer will wait in line before being served.

2. Regal Bank’s policy is that the average waiting time in the line should not exceed five minutes. The bank cannot reduce the time to serve a customer below 4.5 minutes without significantly affecting quality. To reduce average waiting time for the 60 customers it expects to serve each day, the bank decides to keep the counter open for 391.5 minutes each day. Verify that by keeping the counter open for a longer time, the bank will be able to achieve its goal of an average waiting time of 4.5 minutes or less.
3. The bank expects to generate, on average, $36 in additional operating income each day as a result of offering the new services. The teller is paid $12 per hour and is employed in incre¬
ments of an hour (that is, the teller can be employed for five, six, seven hours, and so on, but not for a fraction of an hour). Ifthe bank wants average waiting time to be no more than 4.5 minutes, should the bank offer the new services?