Operations Management
11th Edition
ISBN: 9780132921145
Author: Jay Heizer
Publisher: PEARSON
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Chapter D, Problem 19P
Question
••• D.19 One mechanic services 5 drilling machines for a steel plate manufacturer. Machines break down on an average of once every 6 working days, and breakdowns tend to follow a Poisson distribution. The mechanic can handle an average of one repair job per day. Repairs follow an exponential distribution.
- a. On the average, how many machines are waiting for service?
- b. On the average, how many drills are in running order?
- c. How much would waiting time be reduced if a second mechanic were hired?
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QUESTION 10
MM2 has a queuing problem where customers who line up to pay their selections form the waiting line. The MM2 system consists of an arrival rate of 3 per hour according to a
Poisson distribution, and service times are on average equal to 16 minutes per customer.
What is the number of customers waiting in the queue on average?
O&1.333
Ob.4.0
Oc.0.952
Od32
O.0.152
Question related to gueing theory don't copy
In a restaurant, two types of foods are available. Arival rate of customers is 26 per hour
Poisson and average service time is 6 minutes exponential. The arriving customers can be
served in three ways. The first way is to open two separate counters for the two types of foods.
The second way is to pool the services, and offer both types of foods in both the counters. The
third way is to open a large number (0) of self-service counters for the customers. Which way
will lead to the maximum busy period of the system?
wwm
QUESTION 1
A multiple channel queuing system with a Poisson arrival rate, and an exponential service time distribution has an average arrival rate of 2.5 customers per
hour and an average service time of eighty minutes per customer. A queuing system is described as unstable or overloaded if its utilization rate is greater
than, or equal to one. For the system just described, what is the minimum number of servers required to retain stability i.e., to avoid overloading?
A. 3
B. 2
C. 4
D. 1
QUESTION 2
Customers arrive at the lone check-out desk of a certain convenience store at the average rate of 0.23 per minute. If it takes on average four minutes for
the store manager to serve each customer, how many customers will on average find themselves waiting in the queue?
A. 3.20
B. 0.00351
C. 0.00024
D. 10.58
Chapter D Solutions
Operations Management
Ch. D - Prob. 1DQCh. D - Prob. 2DQCh. D - Question 3. Name the three factors that govern the...Ch. D - Prob. 4DQCh. D - Prob. 5DQCh. D - Prob. 6DQCh. D - Prob. 7DQCh. D - Prob. 8DQCh. D - Prob. 9DQCh. D - Question 10. Describe the behavior of a waiting...
Ch. D - Question 11. Discuss 1he likely outcome of a...Ch. D - Prob. 12DQCh. D - Prob. 13DQCh. D - Prob. 14DQCh. D - Question 15. What happens if two single-server...Ch. D - Prob. 16DQCh. D - Prob. 17DQCh. D - Prob. 1PCh. D - Prob. 2PCh. D - Question D.3 Paul Fenster owns and manages a...Ch. D - Prob. 4PCh. D - Prob. 5PCh. D - Prob. 6PCh. D - Question D.7 Automobiles arrive at the...Ch. D - Question D.8 Virginias Ron McPherson Electronics...Ch. D - Question D.9 Neve Commercial Bank is the only...Ch. D - Question D.10 Beate Klingenberg manages a...Ch. D - Question D.11 Bill Youngdahl has been collecting...Ch. D - Question D.12 The wheat harvesting season in the...Ch. D - Prob. 13PCh. D - Prob. 14PCh. D - Prob. 15PCh. D - Prob. 16PCh. D - Prob. 17PCh. D - Prob. 18PCh. D - Question D.19 One mechanic services 5 drilling...Ch. D - Prob. 20PCh. D - Prob. 21PCh. D - Prob. 22PCh. D - Prob. 23PCh. D - Prob. 24PCh. D - Question New England Foundry For more than 75...Ch. D - Prob. 1.2CSCh. D - New England Foundry For more than 75 years, New...Ch. D - Question The Winter Park Hotel Lori Cook, manager...Ch. D - Question The Winter Park Hotel Lori Cook, manager...
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- Question related to gueing theory don't copy Machines fail at 4 per hour and the cost of non-productive machine is Rs. 282 per hour. A repairman charges Rs. 100 per hour and repairs at 7 per hour. What will be the total queuing costs per hour? Assume M/M/1 queuing system.arrow_forwardQuestion 9 In Littlefield Labs, each order is processed at three stations before being completed and sent to customers. Suppose at the peak demand (i.e., after 180 days in the game) the flow rate is 10 orders per day. And the average inventory at station 1, station 2 and station 3 are 72, 65 and 70 kits, respectively (these include kits being processed as well as those in queues). What is the average lead time (in hours) o complete an order? Please specify your answer in at least 2 decimal points. (Remember 1 order has 60 kits, each day has 24 hours). Nextarrow_forwardQuestion 8 (Atlantic Video) Atlantic Video, a small video rental store in Philadelphia, is open 24 hours a day, and—due to its proximity to a major business school—experiences customers arriving around the clock. A recent analysis done by the store manager indicates that there are 30 customers arriving every hour, with a standard deviation of interarrival times of 2 minutes. This arrival pattern is consistent and is independent of the time of day. The checkout is currently operated by one employee, who needs on average 1.7 minutes to check out a customer. The standard deviation of this check-out time is 3 minutes, primarily as a result of customers taking home different numbers of videos. a. If you assume that every customer rents at least one video (i.e., has to go to the checkout), what is the average time a customer has to wait in line before getting served by the checkout employee, not including the actual checkout time (within 1 minute)? b. If there are no customers requiring…arrow_forward
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