On average, 100 customers arrive per hour at theGotham City Bank. The average service time for eachcustomer is one minute. Service times and interarrivaltimes are exponentially distributed. The manager wantsto ensure that no more than 1% of all customers willhave to wait in line for more than five minutes. If thebank follows the policy of having all customers join asingle line, how many tellers must the bank hire?

On average, 100 customers arrive per hour at theGotham City Bank. The average service time for eachcustomer is one minute. Service times and interarrivaltimes are exponentially distributed. The manager wantsto ensure that no more than 1% of all customers willhave to wait in line for more than five minutes. If thebank follows the policy of having all customers join asingle line, how many tellers must the bank hire?

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 9P

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An average of 100 customers arrive each hour at theGotham City Bank. The average service time for eachcustomer is 1 minute. Service times and interarrival timesare exponential. The manager wants to ensure that no morethan 1% of all customers will have to wait in line for morethan 5 minutes. If the bank follows the policy of having allcustomers join a single line, how many tellers must the bankhire?
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