On average, 100 customers arrive per hour at GothamCity Bank. It takes a teller an average of two minutesto serve a customer. Interarrival and service times areexponentially distributed. The bank currently has fourtellers working. The bank manager wants to compare thefollowing two systems with regard to the average numberof customers present in the bank and the probability that acustomer will spend more than eight minutes in line.■ System 1: Each teller has his or her own line (andno moving between lines is permitted). Arrivingcustomers are equally likely to choose any teller.■ System 2: All customers wait in a single line forthe first available teller.If you were the bank manager, which system wouldyou prefer?

On average, 100 customers arrive per hour at GothamCity Bank. It takes a teller an average of two minutesto serve a customer. Interarrival and service times areexponentially distributed. The bank currently has fourtellers working. The bank manager wants to compare thefollowing two systems with regard to the average numberof customers present in the bank and the probability that acustomer will spend more than eight minutes in line.■ System 1: Each teller has his or her own line (andno moving between lines is permitted). Arrivingcustomers are equally likely to choose any teller.■ System 2: All customers wait in a single line forthe first available teller.If you were the bank manager, which system wouldyou prefer?

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter12: Queueing Models

Section12.5: Analytic Steady-state Queueing Models

Problem 18P

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