A supermarket is trying to decide how many cashregisters to keep open. Suppose an average of 18 customersarrive each hour, and the average checkout time for acustomer is 4 minutes. Interarrival times and service timesare exponential, and the system may be modeled as anM/M/s/GD/∞/∞ queuing system. It costs $20 per hour tooperate a cash register, and a cost of 25¢ is assessed foreach minute the customer spends in the cash register area.How many registers should the store open?

A supermarket is trying to decide how many cashregisters to keep open. Suppose an average of 18 customersarrive each hour, and the average checkout time for acustomer is 4 minutes. Interarrival times and service timesare exponential, and the system may be modeled as anM/M/s/GD/∞/∞ queuing system. It costs $20 per hour tooperate a cash register, and a cost of 25¢ is assessed foreach minute the customer spends in the cash register area.How many registers should the store open?

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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