An ofi ce employs several clerks who create documents and one operator who entersthe document information in a computer system. The group creates documents at a rateof 25 per hour. The operator can enter the information with an average exponentiallydistributed time of two minutes. Assume the population is ini nite, arrivals are Poisson,and queue length is ini nite with FCFS discipline.a. Calculate the percentage utilization of the operator.b. Calculate the average number of documents in the system.c. Calculate the average time in the system.d. Calculate the probability of four or more documents being in the system.e. If another clerk were added, the document origination rate would increase to 30 perhour. What would the expected average number of documents in the system become?Show why.

An ofi ce employs several clerks who create documents and one operator who entersthe document information in a computer system. The group creates documents at a rateof 25 per hour. The operator can enter the information with an average exponentiallydistributed time of two minutes. Assume the population is ini nite, arrivals are Poisson,and queue length is ini nite with FCFS discipline.a. Calculate the percentage utilization of the operator.b. Calculate the average number of documents in the system.c. Calculate the average time in the system.d. Calculate the probability of four or more documents being in the system.e. If another clerk were added, the document origination rate would increase to 30 perhour. What would the expected average number of documents in the system become?Show why.

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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