OPERATIONS MANAGEMENT IN THE SUPPLY CHAIN: DECISIONS & CASES (Mcgraw-hill Series Operations and Decision Sciences)
7th Edition
ISBN: 9780077835439
Author: Roger G Schroeder, M. Johnny Rungtusanatham, Susan Meyer Goldstein
Publisher: McGraw-Hill Education
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Question
Chapter 9, Problem 7P
a)
Summary Introduction
To determine: The upper and LCLs for X bar and R control charts.
b)
Summary Introduction
To determine: The action that should be taken.
c)
Summary Introduction
To discuss: The pros and cons of using a variable control chart instead of an attribute control chart.
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A woodworker is concerned about the quality of the finished appearance of her work. She has finished a total of 50 unit split-willow hand-woven baskets. However, she has found the following number of finish defects in ten units sampled: 4,0,3,1,2,0,1,2,0,2.
Calculate the average number of defects per basket.
If 3-sigma control limits are used, calculate the lower control limit and upper control limit.
An e-commerce website has received some complaints on Billing errors. Managers ask the accounting department to monitor the
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45
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9 10
1 6
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5
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Upper Control Limit
Lower Control Limit
A shirt manufacturer buys clothes by the 100-yard roll from a supplier. For setting a control chart to manage the irregularities (e.g., loose threads and tears), the following data were collected from a sample provided by the supplier.
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1
2
3
4
5
6
7
8
9
10
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3
5
2
6
5
4
6
3
4
5
Which type of control chart should be used? Construct a control chart with two-sigma control limits.
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Explain and show work
Chapter 9 Solutions
OPERATIONS MANAGEMENT IN THE SUPPLY CHAIN: DECISIONS & CASES (Mcgraw-hill Series Operations and Decision Sciences)
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