Operations Management
17th Edition
ISBN: 9781259142208
Author: CACHON, Gérard, Terwiesch, Christian
Publisher: Mcgraw-hill Education,
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Chapter 18, Problem 6PA
Summary Introduction
To determine: Average flow time of the projects in SPT sequence.
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Courtney is a programmer receiving requests each week to analyze a large data base. Five jobs were on her desk Monday morning and
she must decide in what order to write the code. Assume that all jobs arrived today (day 1 and hour 1), in the order shown below. Courtney
has assigned the number of hours required to do the coding as noted. Note that Courtney works an 8-hour day and today is a work day.
Due date
Duration (hours
required)
Job
(hours hence)
A
8
16
2
C
24
10
32
16
E
12
6
In what sequence would the jobs be ranked according to the following decision rules: FCFS, EDD, SPT, LPT?
According to the FCFS rule, the sequence of jobs should be
According to the EDD rule, the sequence of jobs should be
According to the SPT rule, the sequence of jobs should be
According to the LPT rule, the sequence of jobs should be
The following jobs are waiting to be processed at a small machine center.
JOB
10
20
30
40
50
DUE DATE
260
256
260
265
275
DURATION (DAYS)
According to the LPT rule, the sequence of jobs should be 10, 50, 40, 20, 30
b) What is the average completion (flow) time?
The average completion (flow) time is 62.8 days (round your response to one decimal place)
c) What is the average job lateness?
The average job lateness is 11.0 days (round your response to one decimal place).
d) What is the average number of jobs in the system?
The average number of jobs in the system is jobs (round your response to one decimal place).
28
12
8
18
22
D
Points: 2 of 4
All dates are specified as manufacturing planning calendar days. Assume that all jobs arrived on day 200 (yesterday) in the order shown but are not scheduled to begin until day 201 (today).
a) Sequence the jobs according to LPT
state whether or not each situation would be considered “compensable time” (and why or why not).
An employee of a fast food chain has to arrive at work 15 minutes early to change into the“mascot” costume and it typically takes another 15 minutes at the end of the shift to change outof the costume and properly store it. Due to the cost of the costume, employees are notallowed to take the costume home. The “mascots” typically work from 10am – 2pm, to coverthe lunch rush periods. How much time would be “compensable” for the mascots, assumingthe conditions/schedule listed above?2) George is a Radiology Technician at a local hospital and when on call, is required to be nofurther than 30 minutes away from the facility. Is the “on call” time, compensable?
Chapter 18 Solutions
Operations Management
Ch. 18 - Prob. 1CQCh. 18 - Prob. 2CQCh. 18 - Prob. 3CQCh. 18 - Prob. 4CQCh. 18 - Prob. 5CQCh. 18 - Prob. 6CQCh. 18 - With weighted shortest processing time, jobs are...Ch. 18 - Prob. 8CQCh. 18 - Prob. 9CQCh. 18 - Prob. 10CQ
Ch. 18 - Prob. 11CQCh. 18 - Prob. 12CQCh. 18 - Prob. 13CQCh. 18 - Prob. 14CQCh. 18 - Prob. 15CQCh. 18 - Prob. 16CQCh. 18 - Prob. 1PACh. 18 - Prob. 2PACh. 18 - Prob. 3PACh. 18 - Prob. 4PACh. 18 - Prob. 5PACh. 18 - Prob. 6PACh. 18 - Prob. 7PACh. 18 - Prob. 8PACh. 18 - Prob. 9PACh. 18 - Prob. 10PACh. 18 - Prob. 11PACh. 18 - Prob. 12PACh. 18 - Prob. 13PACh. 18 - Prob. 14PACh. 18 - Prob. 15PACh. 18 - Prob. 1CCh. 18 - Prob. 2CCh. 18 - Prob. 3CCh. 18 - Prob. 4C
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