Production and Operations Analysis, Seventh Edition
7th Edition
ISBN: 9781478623069
Author: Steven Nahmias, Tava Lennon Olsen
Publisher: Waveland Press, Inc.
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Suppose that arrivals to a hairdresser follow a Poisson process with mean 12 customers per hour. Calculate the probabilities of (a) no customers in 20 minutes; (b) exactlyone customer in 5 minutes; (c) exactly 12 customers in a hour; and (d) fewer than threecustomers in 10 minutes.
A cafeteria serving line has a coffee urn from which customers serve themselves. Arrivals at the urn follow a Poisson distribution at the rate of 4.0 per minute. In serving themselves, customers take about 11 seconds, exponentially distributed.
a. How many customers would you expect to see on the average at the coffee urn?
b. How long would you expect it to take to get a cup of coffee?
c. What percentage of time is the urn being used?
d. What is the probability that three or more people are in the cafeteria?
e. If the cafeteria installs an automatic vendor that dispenses a cup of coffee at a constant time of 11 seconds, how many customers would you expect to see at the coffee urn (waiting and/or pouring coffee)?
f.If the cafeteria installs an automatic vendor that dispenses a cup of coffee at a constant time of 11 seconds, how long would you expect it to take (in minutes) to get a cup of coffee, including waiting time?
An average of 12 jobs per hour arrive at our departmentalprinter.a Use two different computations (one involving thePoisson and another the exponential random variable) todetermine the probability that no job will arrive duringthe next 15 minutes.
b What is the probability that 5 or fewer jobs will ar-rive during the next 30 minutes?
Chapter 7 Solutions
Production and Operations Analysis, Seventh Edition
Ch. 7.1 - Prob. 1PCh. 7.1 - Prob. 2PCh. 7.1 - Prob. 3PCh. 7.1 - Prob. 4PCh. 7.1 - Prob. 5PCh. 7.1 - Prob. 6PCh. 7.1 - Prob. 7PCh. 7.2 - Prob. 8PCh. 7.2 - Prob. 9PCh. 7.2 - Prob. 10P
Ch. 7.3 - Prob. 11PCh. 7.3 - Prob. 12PCh. 7.3 - Prob. 13PCh. 7.3 - Prob. 14PCh. 7.3 - Prob. 15PCh. 7.3 - Prob. 16PCh. 7.3 - Prob. 18PCh. 7.4 - Prob. 19PCh. 7.4 - Prob. 21PCh. 7.4 - Prob. 22PCh. 7.4 - Prob. 23PCh. 7.5 - Prob. 24PCh. 7.5 - Prob. 25PCh. 7.5 - Prob. 26PCh. 7.5 - Prob. 27PCh. 7.8 - Prob. 28PCh. 7.8 - Prob. 29PCh. 7.8 - Prob. 30PCh. 7.8 - Prob. 32PCh. 7.8 - Prob. 34PCh. 7.8 - Prob. 35PCh. 7.8 - Prob. 36PCh. 7 - Prob. 38APCh. 7 - Prob. 39APCh. 7 - Prob. 40APCh. 7 - Prob. 41APCh. 7 - Prob. 42APCh. 7 - Prob. 43APCh. 7 - Prob. 44APCh. 7 - Prob. 45APCh. 7 - Prob. 46AP
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