A snack stand with one seller is set in a university campus. Customers arrive at the snack standat an average of one every 5 minutes following Poisson distribution. The service of the sellerfor each customer can be described by an exponential distribution with a mean of 4 minutes.Q2.1 How long is the average waiting time in queue?Q2.2 What is the probability that there are at least four customers in the system?Q2.3 If the waiting cost for each customer is $200/h and the cost for each seller is $240/h, is itnecessary to hire more sellers? If yes, how many new sellers should be hired?Q2.4 If one snack selling machine is set to replace the snack stand, the service time for eachcustomer is constant (2 minute). What is the average time a customer spends in the system afterthe machine is used?

Given, Arrival rate, λ= 1÷5=0.2 customers per minute Service rate, μ =1÷4=0.25 customers per minute…

Answered: A snack stand with one seller is set in…

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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