Practical Management Science, Loose-leaf Version
5th Edition
ISBN: 9781305631540
Author: WINSTON, Wayne L.; Albright, S. Christian
Publisher: Cengage Learning
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Chapter 13.5, Problem 19P
Summary Introduction
To determine: The way to minimize the expected hourly cost.
Introduction: In order to predict the waiting time and length of the queue, queueing model will be framed. Queueing theory is the mathematical model that can be used for the decision-making process regarding the resources required to provide a service.
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A supermarket is trying to decide how many cash registers to keep open. Suppose an average of 18 customers arrive each hour, and the average checkout time for a customer is four minutes. Interarrival times and servicetimes are exponentially distributed, and the system can be modeled as an M/M/s system. (In contrast to the situation at most supermarkets, we assume that all customers wait in a single line.) It costs $20 per hour tooperate a cash register, and a cost of $0.25 is assessed for each minute the customer spends in the cash register area (in line or being served). How many registers should the store open to minimize the expected hourly cost?
A supermarket is trying to decide how many cashregisters to keep open. Suppose an average of 18customers arrive each hour, and the average checkouttime for a customer is four minutes. Interarrival timesand service times are exponentially distributed, andthe system can be modeled as an MyMys system.(In contrast to the situation at most supermarkets,we assume that all customers wait in a single line.)It costs $20 per hour to operate a cash register,and a cost of $0.25 is assessed for each minute thecustomer spends in the queue. How many registersshould the store open to minimize the expectedhourly cost?
Many of a bank’s customers use its automated banking machine (ABM). During the early eveninghours in the summer months, customers arrive at an ABM at the rate of one every other minute(assume Poisson). Each customer spends an average of 99 seconds completing the transaction.Transaction times are exponentially distributed. Assume that the length of the queue is not aconstraint.
Determine the average time customers spend at the machine, including waiting in line and completing transactions.
Determine the probability that a customer will not have to wait upon arrival at the ABM.
Determine the utilization of the ABM.
Chapter 13 Solutions
Practical Management Science, Loose-leaf Version
Ch. 13.3 - Prob. 1PCh. 13.3 - Prob. 2PCh. 13.3 - Prob. 3PCh. 13.3 - Prob. 4PCh. 13.4 - Prob. 5PCh. 13.4 - Prob. 6PCh. 13.4 - Prob. 7PCh. 13.4 - Prob. 8PCh. 13.5 - Prob. 9PCh. 13.5 - Prob. 10P
Ch. 13.5 - Prob. 11PCh. 13.5 - Prob. 12PCh. 13.5 - Prob. 13PCh. 13.5 - Prob. 14PCh. 13.5 - Prob. 15PCh. 13.5 - Prob. 16PCh. 13.5 - Prob. 17PCh. 13.5 - Prob. 18PCh. 13.5 - Prob. 19PCh. 13.5 - Prob. 20PCh. 13.5 - Prob. 21PCh. 13.5 - Prob. 22PCh. 13.5 - Prob. 23PCh. 13.5 - Prob. 24PCh. 13.5 - Prob. 25PCh. 13.5 - Prob. 26PCh. 13.5 - Prob. 27PCh. 13.5 - Prob. 28PCh. 13.5 - Prob. 29PCh. 13.5 - Prob. 30PCh. 13.5 - Prob. 31PCh. 13.5 - Prob. 32PCh. 13.5 - Prob. 33PCh. 13.5 - Prob. 34PCh. 13.5 - Prob. 35PCh. 13.5 - Prob. 36PCh. 13.5 - Prob. 37PCh. 13 - Prob. 46PCh. 13 - Prob. 47PCh. 13 - Prob. 48PCh. 13 - Prob. 49PCh. 13 - Prob. 50PCh. 13 - Prob. 51PCh. 13 - Prob. 52PCh. 13 - Prob. 54PCh. 13 - Prob. 58PCh. 13 - Prob. 59P
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