Practical Management Science
6th Edition
ISBN: 9781337406659
Author: WINSTON, Wayne L.
Publisher: Cengage,
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Chapter 12.5, Problem 14P
Summary Introduction
To determine: The change L, W, LQ, and WQ if L and W is doubled in formula.
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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We are in a M/M/1/3 queueing system in which we
wish to determine the cost of operating the system. Each customer in the queue costs us
$100 per hour and each customer being served costs us $50 an hour. Customers arrive at a
rate of 4 per hour and the server can serve customers at a rate of 5 per hour. The following
table in the picture provides Pn values, W, and Wq:
An emergency room (ER) at a Prisma Health Hospital has 10 total
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arrive to the ER at a rate of 5 per hour. Therefore, we have that λn = 6 for n = 0, 1, . . . , 9
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of this queueing system. The amount of time required for an ER doctor to treat a patient
is exponentially distributed with a mean of .4 hours. We seek the minimum number of ER
doctors so that the expected time of a patient waiting to be seen (so the Wq) is less than
or equal to 15 minutes (.25 hours). You should begin by analyzing s = 1 and show any
calculations that were used to determine Wq for each number of servers that you considered
until you meet the target metric.
MacBurger’s is attempting to determine how manyservers (or lines) should be available during the breakfastshift. During each hour, an average of 100 customers arriveat the restaurant. Each line or server can handle an averageof 50 customers per hour. A server costs $5 per hour, andthe cost of a customer waiting in line for 1 hour is $20.Assuming that an M/M/s/GD/∞/∞ model is applicable,determine the number of lines that minimizes the sum ofdelay and service costs.
Chapter 12 Solutions
Practical Management Science
Ch. 12.3 - Prob. 1PCh. 12.3 - Explain the basic relationship between the...Ch. 12.3 - Prob. 3PCh. 12.3 - Prob. 4PCh. 12.4 - Prob. 5PCh. 12.4 - Prob. 6PCh. 12.4 - Prob. 7PCh. 12.4 - Prob. 8PCh. 12.5 - Prob. 9PCh. 12.5 - Prob. 10P
Ch. 12.5 - Prob. 11PCh. 12.5 - Prob. 12PCh. 12.5 - Prob. 13PCh. 12.5 - Prob. 14PCh. 12.5 - Prob. 15PCh. 12.5 - Prob. 16PCh. 12.5 - Prob. 17PCh. 12.5 - Prob. 18PCh. 12.5 - Prob. 19PCh. 12.5 - Prob. 20PCh. 12.5 - Prob. 21PCh. 12.5 - Prob. 22PCh. 12.5 - On average, 100 customers arrive per hour at the...Ch. 12.5 - Prob. 24PCh. 12.5 - Prob. 25PCh. 12.5 - Prob. 26PCh. 12.5 - Prob. 27PCh. 12.5 - Prob. 28PCh. 12.5 - Prob. 29PCh. 12.5 - Prob. 30PCh. 12.5 - Prob. 31PCh. 12.5 - Prob. 32PCh. 12.5 - Prob. 33PCh. 12.5 - Prob. 34PCh. 12.5 - Prob. 35PCh. 12.5 - Two one-barber shops sit side by side in Dunkirk...Ch. 12.5 - Prob. 37PCh. 12 - Prob. 46PCh. 12 - Prob. 47PCh. 12 - Prob. 48PCh. 12 - Prob. 49PCh. 12 - Prob. 50PCh. 12 - Prob. 51PCh. 12 - Prob. 52PCh. 12 - Prob. 54PCh. 12 - Prob. 56PCh. 12 - Prob. 57PCh. 12 - Prob. 58PCh. 12 - Prob. 59PCh. 12 - Prob. 60PCh. 12 - Prob. 61P
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