The Decision Sciences Department is trying to determine whether to rent a slow or a fast copier. The department believes that an employee’s time is worth $15 per hour. The slow copier rents for $4 per hour, and it takes an employee an average of 10 minutes to complete copying. The fast copier rents for $15 per hour, and it takes an employee an average of six minutes to complete copying. On average, four employees per hour need to use the copying machine. (Assume the copying times and interarrival times to the copying machine are exponentially distributed.) Which machine shouldthe department rent to minimize expected total cost per hour?

The Decision Sciences Department is trying to determine whether to rent a slow or a fast copier. The department believes that an employee’s time is worth $15 per hour. The slow copier rents for $4 per hour, and it takes an employee an average of 10 minutes to complete copying. The fast copier rents for $15 per hour, and it takes an employee an average of six minutes to complete copying. On average, four employees per hour need to use the copying machine. (Assume the copying times and interarrival times to the copying machine are exponentially distributed.) Which machine shouldthe department rent to minimize expected total cost per hour?

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 27P

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The Decision Sciences Department is trying todetermine whether to rent a slow or a fast copier. Thedepartment believes that an employee’s time is worth $15per hour. The slow copier rents for $4 per hour and it takesan employee an average of 10 minutes to complete copying(exponentially distributed). The fast copier rents for $15 perhour and it takes an employee an average of 6 minutes tocomplete copying. An average of 4 employees per hour needto use the copying machine (interarrival times areexponential). Which machine should the department rent?
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