Pristol, a food retailer, supplies food for vending machines at a university. As the machines are abused by university students, management has to repair them. The machines break down at an average of three per hour and the breakdowns are Poisson distributed. The downtime costs the company $25/hr and each maintenance worker earns $4/hr. One worker can service the machines at a rate of five per hour, exponentially distributed; two workers working together can service at seven per hour, exponentially distributed; and a crew of three can service at eight per hour, exponentially distributed. How large should the crew size be for optimal cost?

Pristol, a food retailer, supplies food for vending machines at a university. As the machines are abused by university students, management has to repair them. The machines break down at an average of three per hour and the breakdowns are Poisson distributed. The downtime costs the company $25/hr and each maintenance worker earns $4/hr. One worker can service the machines at a rate of five per hour, exponentially distributed; two workers working together can service at seven per hour, exponentially distributed; and a crew of three can service at eight per hour, exponentially distributed. How large should the crew size be for optimal cost?

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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