1. Cachon and Terweisch 8.5: Atlantic Video, a small video rental store in Philadelphia, is open 24 hours a day and experiences customers arriving around the clock. A recent analysis done by the store manager indicates that there are 30 customers arriving every hour, with a standard deviation of interarrival times of 2 minutes. This arrival pattern is consistent throughout the day. The checkout is currently operated by one employee, who needs on average 1.7 minutes to check out a customer. The standard deviation of this checkout time is 3 minutes.
(c) What is the average number of customers who are at the checkout desk, either waiting or currently being served?
(d) Now assume for this question only that 10 percent of the customers do not rent a video at all and therefore do not have to go through checkout. What is the average time a customer has to wait in line before getting served by the checkout employee, not including the actual checkout time? Assume that the coefficient of variation for the arrival process remains the same as before.