Operations Management
13th Edition
ISBN: 9781259667473
Author: William J Stevenson
Publisher: McGraw-Hill Education
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Question
Chapter 18, Problem 13P
a)
Summary Introduction
To determine: Whether the third crew member will be economical.
b.
Summary Introduction
To determine: Would the fourth member be justifiable.
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Trucks arrive at the loading dock of a wholesale grocer at the rate of 1.2 per hour. A single crewconsisting of two workers can load a truck in about 30 minutes. Crew members receive $10 perhour in wages and fringe benefits, and trucks and drivers reflect an hourly cost of $60. The manager is thinking of adding another member to the crew. The service rate would then be 2.4 trucksper hour. Assume rates are Poisson.a. Would the third crew member be economical?b. Would a fourth member be justifiable if the resulting service capacity were 2.6 trucks per hour?
A server operates with 90 % utilization. Coefficient of variation of service process is 0.6. Coefficient of variation of arrival process is 0.8. Average processing time is 4 minutes. What is the average time a customer spends in the system using the single server queuing model ? Show all formulas used, calculations and results.
A vending machine dispenses hot chocolate or coffee. Service time is 30 seconds per cup and is constant. Customers arrive at a mean rate of 76 per hour, and this rate is Poisson-distributed.
a.
Determine the average number of customers waiting in line. (Round your answer to 2 decimal places.)
Average number of customer
b.
Determine the average time customers spend in the system. (Do not round intermediate calculations. Round your answer to 2 decimal places.)
Average time
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c.
Determine the average number of customers in the system. (Do not round intermediate calculations. Round your answer to 2 decimal places.)
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Chapter 18 Solutions
Operations Management
Ch. 18 - Prob. 1DRQCh. 18 - Why do waiting lines form even though a service...Ch. 18 - Prob. 3DRQCh. 18 - Prob. 4DRQCh. 18 - What approaches do supermarkets use to offset...Ch. 18 - Prob. 6DRQCh. 18 - Prob. 7DRQCh. 18 - Prob. 8DRQCh. 18 - Prob. 9DRQCh. 18 - Prob. 1TS
Ch. 18 - Prob. 2TSCh. 18 - Prob. 3TSCh. 18 - Prob. 1CTECh. 18 - Prob. 2CTECh. 18 - Prob. 3CTECh. 18 - The owner of Eat Now Restaurant implemented an...Ch. 18 - Prob. 5CTECh. 18 - Prob. 1PCh. 18 - Prob. 2PCh. 18 - Prob. 3PCh. 18 - Prob. 4PCh. 18 - Prob. 5PCh. 18 - Prob. 6PCh. 18 - Prob. 7PCh. 18 - Prob. 8PCh. 18 - Prob. 9PCh. 18 - Prob. 10PCh. 18 - Prob. 11PCh. 18 - Prob. 12PCh. 18 - Prob. 13PCh. 18 - Prob. 14PCh. 18 - Prob. 15PCh. 18 - A priority waiting system assigns arriving...Ch. 18 - Prob. 17PCh. 18 - Prob. 18PCh. 18 - Prob. 1CQ
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