A crew of mechanics at the Highway Department garage repair vehicles that break down at an average of 15 vehicles per hour (approximately Poisson in nature). The mechanic crew can service an average of 3 vehicles every 10 minutes with a repair time distribution that approximates an exponential distribution. The crew cost is approximately $100 per hour. The cost associated with lost productivity from the breakdown is estimated at $25 per vehicle per hour (or any fraction thereof). Which is cheaper, the existing system with one service crew, or a revised system with two service crews? The average waiting time for adding the second crew is 0.02.

A crew of mechanics at the Highway Department garage repair vehicles that break down at an average of 15 vehicles per hour (approximately Poisson in nature). The mechanic crew can service an average of 3 vehicles every 10 minutes with a repair time distribution that approximates an exponential distribution. The crew cost is approximately $100 per hour. The cost associated with lost productivity from the breakdown is estimated at $25 per vehicle per hour (or any fraction thereof). Which is cheaper, the existing system with one service crew, or a revised system with two service crews? The average waiting time for adding the second crew is 0.02.

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 26P

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