(AAFCU) operates an ATM on the third floor of the building. Over the course of the 10 hour day, customers arrive at the ATM at the rate of 80 per hour. Customers spend on average 36 seconds at the ATM. AAFCU leases the current ATM from the NCR Corporation, and NCR has a new machine that can serve 50% more customers per hour. AAFCU is considering replacing the current ATM with the new ATM. The arrival and service processes are such that this is an M/M/1 queue. What is the average waiting time in the QUEUE for the CURRENT ATM? (Round to nearest SECOND, eg 31):
A) What is the NEW ATM average time (in seconds) in the QUEUE? (Round to nearest SECOND, eg 31)
B) AAFCU is concerned that the NEW machine will not be utilized enough to make it worthwhile. He is considering a marketing plan to encourage ATM usage. What NEW ATM HOURLY arrival rate (#/Hr) is necessary to achieve the utilization rate of the CURRENT ATM? (Provide whole number arrivals per Hr, eg. 76)
C) AAFCU leases the CURRENT ATM for only $200/day. On the other hand, NCR charges $2000/day for the NEW ATM. AAFCU estimates the cost of Customer Time in their SYSTEM at $500/Day. Assume ORIGINAL arrival rates from PS1.1. What is the Total Cost (per DAY) of the CURRENT ATM? (Round to the nearest WHOLE dollar)
D) What is the Total Cost (per DAY) of the NEW ATM? (Round to the nearest WHOLE dollar
E) Based on cost alone, should AAFCU stay with the CURRENT ATM or replace it with the NEW ATM?
F) Assume the NEW ATM lease is negotiable. At what daily lease cost of the NEW ATM is Mr. Strebe INDIFFERENT between the two machines? (Round to the nearest WHOLE Dollar)