A supermarket has four girls ringing sales at the counters. If the service time for each customer is exponential with mean 4 minutes, and if people arrive in a Poisson fashion at the rate of 10 per hour, calculate i.The average number of customers in the system. ii.The average time a customer spends in the system. iii.The average queue length iv.The average waiting time for customers. v.The expected percentage of idle time for each girl vi.The probability that at least a girl is waiting for the customer.

Answered: The average number of customers in the…

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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i.	The average number of customers in the system.
ii.	The average time a customer spends in the system.
iii.	The average queue length
iv.	The average waiting time for customers.
v.	The expected percentage of idle time for each girl
vi.	The probability that at least a girl is waiting for the customer.

The average number of customers in the system. ii. The average time a customer spends in the system. iii. The average queue length