Spreadsheet Modeling & Decision Analysis: A Practical Introduction To Business Analytics, Loose-leaf Version
8th Edition
ISBN: 9781337274852
Author: Ragsdale, Cliff
Publisher: South-Western College Pub
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[Queuing Theory - Operation research]
The take-out counter at an ice-cream parlor is serviced by one attendant. Customers arrive according to a Poisson process, at a mean arrival rate of 30 per hour. They are serviced on a FCFS basis, and because of the quality of the ice cream, they are willing to wait if necessary. The service time per customer appears to be exponentially distributed, with a mean of 1.5 minutes. Determine the following:
(a) probability that the system is idle
(b) average number of customers in the system
(c) amount of time a customer should expect to wait before service
(d) probability that a customer will have to spend more than 15 minutes in the queue
Benny the Barber owns a one-chair shop. At barber college, they told Benny that his customers would exhibit a Poisson arrival distribution and that he would provide an exponential service distribution. His market survey data indicate that customers arrive at a rate of two per hour. It will take Benny an average of 20 minutes to give a haircut. Based on these figures, find the following:
Part (a): The average number of customers waiting.
Arrival Time, λ =2 customers per hour
Service Time, μ = 20 minute, or 60/20= 3 customer per hour
Lq = (2)2 / 3*(3-2) = 1.333 customers
Part (b): The average time a customer waits.
Wq= 1.333/2=0,665 \~ 0,67 or 40 minutes
Part (c): The average time a customer is in the shop.
LS = 2/ 3-2 =2 customers. WS = 2/2 = 1 hour
Part (d): The average utilization of Benny’s time.
P= λ/ μ = 2/3=0,666 percent ~ 0,67 %
Benny the Barber (see Question 1) is considering the addition of a second chair. Customers would be selected for a haircut on a FCFS basis from…
How would you apply Queuing Analysis in the Engineering field?
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Round your answer to four decimal places.L = fill in the blank 2 What percentage of calls receive a busy signal for the current telephone system with two extension lines? Round your answer to two decimal…arrow_forward
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