Operations Management: Processes and Supply Chains (12th Edition) (What's New in Operations Management)
12th Edition
ISBN: 9780134741062
Author: Lee J. Krajewski, Manoj K. Malhotra, Larry P. Ritzman
Publisher: PEARSON
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Question
Chapter 3, Problem 27P
(a)
Summary Introduction
Interpretation: It is to be determined that the call center access time is in statistical control.
Concept Introduction:
The X-chart is used to determine the central tendency of the process. By using the X-chart it easy to determine the abnormalities of the process along with the errors which are responsible for these errors.
(b)
Summary Introduction
Interpretation: The capability of the process is to be determined when three-sigma performance is desired.
Concept Introduction:
The X-chart is used to determine the central tendency of the process. By using the X-chart it easy to determine the abnormalities of the process along with the errors which are responsible for these errors.
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Designing an x -Chart Using the Process Standard DeviationThe Sunny Dale Bank monitors the time required to serve customers at the drive-through window because it is an important quality factor in competing with other banks in the city. After analyzing the data gathered in an extensive study of the window operation, bank management determined that the mean time to process a customer at the peak demand period is 5 minutes, with a standard deviation of 1.5 minutes. Management wants to monitor the mean time to process a customer by periodically using a sample size of six customers. Assume that the process variability is in statistical control. Design an x-chart that has a type I error of 5 percent. That is, set the control limits so that there is a 2.5 percent chance a sample result will fall below the LCL and a 2.5 percent chance that a sample result will fall above the UCL. After several weeks of sampling, two successive samples came in at 3.70 and 3.68 minutes, respectively. Is the…
Southern Mills Company
One of the stages in the process of making denim cloth at the Southern Mills Company is to spin
cotton yarn onto spindles for subsequent use in the weaving process. Occasionally the yarn breaks
during the spinning process, and an operator ties it back together. Some number of breaks is
considered normal; however, too many breaks may mean that the yarn is of poor quality. In order to
monitor this process, the quality-control manager randomly selects a spinning machine each hour
and checks the number of breaks during a 15-minute period. Following is a summary of the
observations for the past 20 hours.
Construct a c-chart using 3 limits for this process and indicate if the process was out of control at
any time.
Number of
Number of
Sample
Breaks
Sample
Breaks
1
3
11
2
12
4
3
4
13
6
1
14
7
5
5
15
8
6
3
16
6
7
2
17
5
8
4
18
7
19
8
10
2
20
6
While analyzing their annual sales data (liters of wine sold per year) for the past 30
years, a vineyard found that after taking four successive differences, the resulting data had a
mean of 2458 liters and looked like a stationary process (e.g. white noise). If the actual data for
the past four years were 2018 - 2134 liters, 2017 - 2403 liters, 2016 - 2076 liters, and 2015 - 2290
liters. What would be a reasonable forecast for sales in 2019? Explain.
Chapter 3 Solutions
Operations Management: Processes and Supply Chains (12th Edition) (What's New in Operations Management)
Ch. 3 - Should a very pricey handcrafted object of beauty...Ch. 3 - Prob. 2DQCh. 3 - Prob. 3DQCh. 3 - Prob. 1PCh. 3 - Prob. 2PCh. 3 - Prob. 3PCh. 3 - Prob. 4PCh. 3 - Prob. 5PCh. 3 - Prob. 6PCh. 3 - Prob. 7P
Ch. 3 - Prob. 8PCh. 3 - Prob. 9PCh. 3 - Prob. 10PCh. 3 - Prob. 11PCh. 3 - Prob. 12PCh. 3 - Prob. 13PCh. 3 - Prob. 14PCh. 3 - Prob. 15PCh. 3 - Prob. 16PCh. 3 - Prob. 17PCh. 3 - Prob. 18PCh. 3 - Prob. 19PCh. 3 - Prob. 20PCh. 3 - Prob. 21PCh. 3 - Prob. 26PCh. 3 - Prob. 27PCh. 3 - Prob. 28PCh. 3 - Prob. 29PCh. 3 - Prob. 31PCh. 3 - Prob. 1AMECh. 3 - Prob. 2AMECh. 3 - Prob. 3AMECh. 3 - Prob. 4AMECh. 3 - Prob. 5AMECh. 3 - Prob. 1VCCh. 3 - Prob. 2VC
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