Golden Muffler Shop’s owner is interested in cost factors as well as the queuing parameters computed in Example D1. He estimates that the cost of customer waiting time, in terms of customer dissatisfaction and lost goodwill, is $15 per hour spent waiting in line. Jones, the mechanic, is paid $11 per hour.

APPROACH c First compute the average daily customer waiting time, then the daily salary for Jones, and finally the total expected cost.