4. Refer to the data in Problem C.2. The owner of the coffee shop at the student recreation center, Amanda Murdock, is interested in computing the per-day total cost of the waiting line system at the coffee shop. She has estimated that the cost of waiting time associated with a dissatisfied student and loss of goodwill is $15 per hour, and the employee at the coffee shop is paid $10 an hour. Assume that the shop is open 10 hours per day. Given this information and the data in Problem C.2, compute the following: a. Average customer waiting time cost per day in the queue b. Total expected costs per day for the waiting line system pie C2 EXAMPLE C.2: The owner of the Golden Beach Amusement Park, Lara Brown, is interested in computing the per-day total cost of the waiting line system for entry into the amusement park. She has estimated the cost of customer waiting time associated with dissatisfied customers and loss of goodwill is $12 per hour. The employee at the service booth in the park is paid $8 an hour. Assume the park is open 10 hours per day. Given the above information and the data in Example C.1, calculate the following: a. Average customer waiting time cost per day in the queue b. Total expected costs per day for the waiting line system Solution To compute the average customer waiting time cost in the queue, we should first compute the average time a customer spends waiting in line for service (W.). This is given by w 19 _2 (-2) L 2 2.25 15 - = 0.15 hours per customer Given an average of 15 customer arrivals per hour, the average number of customer arrivals per day to the park is 15 x 10 = 150 customers. Thus, the average total number of hours cus- tomers wait for entry into the park per day is 0.15 x 150 = 22.5 hours a. The average customer waiting time cost in the queue is 22.5 x $12 = $270 In addition to the above cost, the only other cost that Lara Brown has to compute is the capacity- related cost associated with the service booth employee for the park. This is the hourly salary of $8 paid to the employee. Hence, the total capacity-related cost per day is $8 x 10 hours = $80. Thus b. Total expected costs per day for the waiting line system are Total expected costs per day = Average customer waiting time cost per day + Capacity-related cost per day = $270 + $80 = $350