A grocery store has three open checkout counters. There is a single queue leading up to these three counters. On average, 45 shoppers arrive at this queue. The coefficient of variation of the interarrival time is equal to 1. The average service capacity of each of the three servers is 18 customers per hour, and the coefficient of variation of service time distribution for each server is 3. (a) (3 points) What is the percentage decrease in capacity utilization when one more checkout lane is added to the system? (b) (7 points) On average, how many customers are waiting in the queue?

A grocery store has three open checkout counters. There is a single queue leading up to these three counters. On average, 45 shoppers arrive at this queue. The coefficient of variation of the interarrival time is equal to 1. The average service capacity of each of the three servers is 18 customers per hour, and the coefficient of variation of service time distribution for each server is 3. (a) (3 points) What is the percentage decrease in capacity utilization when one more checkout lane is added to the system? (b) (7 points) On average, how many customers are waiting in the queue?

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 18P

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