Practical Operations Management
2nd Edition
ISBN: 9781939297136
Author: Simpson
Publisher: HERCHER PUBLISHING,INCORPORATED
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Question
Chapter 5, Problem 2.2Q
Summary Introduction
Interpretation: Probability that the customer finds no car in the lane.
Concept introduction: The M/M/1 queue assumes poison arrivals, exponential service times, and a single server serving customers in an FCFS fashion. Poisson arrivals are a reasonably good assumption for unscheduled systems. Further, if there is a mix of many different types of jobs the exponential distribution can be realistic for service times. Otherwise, it tends to be too variable of a distribution.
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If the restaurant runs a sale and the customer arrival rate increases by 20 percent how would this change the total time expected to serve a customer? How would this change the average number of cars in the drive-thru line?
Customer arrive at one-window drive in bank according to Poisson distribution with mean 10 per hour. Service time per customer is exponential with mean 5 minutes. There are three spaces in front of the window, including the car being served. Other arriving cars can wait outside these three spaces.
A. What is the probability that an arriving customer can enter one of these three spaces?
B. What is the probability that an arriving customer is expected to wait outside the three spaces.
C.How long is an arriving customer expected to wait before starting service.
Willow Brook National Bank operates a drive-up teller window that allows customers to complete bank transactions without getting out of their cars. On weekday mornings, arrivals to the drive-up teller window occur at random, with an arrival rate of 24 customers per hour or 0.4 customers per minute.
What is the mean or expected number of customers that will arrive in a five-minute period?λ = fill in the blank 1 per five minute period
Assume that the Poisson probability distribution can be used to describe the arrival process. Use the arrival rate in part (a) and compute the probabilities that exactly 0, 1, 2, and 3 customers will arrive during a five-minute period. If required, round your answers to four decimal places.
x
P(x)
0
fill in the blank 2
1
fill in the blank 3
2
fill in the blank 4
3
fill in the blank 5
Delays are expected if more than three customers arrive during any five-minute period. What is the probability that delays will occur? If required, round your…
Chapter 5 Solutions
Practical Operations Management
Ch. 5 - Prob. 1DQCh. 5 - Prob. 2DQCh. 5 - Prob. 3DQCh. 5 - Prob. 4DQCh. 5 - Prob. 5DQCh. 5 - Prob. 6DQCh. 5 - Prob. 7DQCh. 5 - Prob. 1PCh. 5 - Prob. 2PCh. 5 - Prob. 3P
Ch. 5 - Prob. 4PCh. 5 - Prob. 5PCh. 5 - Prob. 6PCh. 5 - Prob. 7PCh. 5 - Prob. 8PCh. 5 - Prob. 9PCh. 5 - Prob. 10PCh. 5 - Prob. 11PCh. 5 - Prob. 12PCh. 5 - Prob. 13PCh. 5 - Prob. 14PCh. 5 - Prob. 15PCh. 5 - Prob. 16PCh. 5 - Prob. 17PCh. 5 - Prob. 18PCh. 5 - Prob. 19PCh. 5 - Prob. 20PCh. 5 - Prob. 21PCh. 5 - Prob. 22PCh. 5 - Prob. 23PCh. 5 - Prob. 24PCh. 5 - Prob. 25PCh. 5 - Prob. 26PCh. 5 - Prob. 27PCh. 5 - Prob. 28PCh. 5 - Prob. 29PCh. 5 - Prob. 30PCh. 5 - Prob. 31PCh. 5 - Prob. 32PCh. 5 - Prob. 33PCh. 5 - Prob. 34PCh. 5 - Prob. 35PCh. 5 - Prob. 36PCh. 5 - Prob. 37PCh. 5 - Prob. 38PCh. 5 - Prob. 1.1QCh. 5 - Prob. 1.2QCh. 5 - Prob. 1.3QCh. 5 - Prob. 1.4QCh. 5 - Prob. 2.1QCh. 5 - Prob. 2.2QCh. 5 - Prob. 2.3QCh. 5 - Prob. 3.1QCh. 5 - Prob. 3.2QCh. 5 - Prob. 3.3QCh. 5 - Prob. 3.4Q
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