Production and Operations Analysis, Seventh Edition
7th Edition
ISBN: 9781478623069
Author: Steven Nahmias, Tava Lennon Olsen
Publisher: Waveland Press, Inc.
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Chapter 12.2, Problem 9P
Summary Introduction
Interpretation: Control Limits needs to be determined with the help of given data.
Concept Introduction: X bar chart monitors the change in mean over time helps organizations makes better improvement decisions.
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Students have asked these similar questions
At Webster Chemical Company, lumps in the caulking compound could cause difficulties in dispensing a smooth bead from the tube. Even when the process is in control, an average of four lumps per tube of caulk will remain. Testing for the presence of lumps destroys the product, so an analyst takes random samples. The following results are obtained:
Tube No.
Lumps
Tube No.
Lumps
Tube No.
Lumps
1
6
5
6
9
5
2
5
6
4
10
0
3
0
7
1
11
9
4
4
8
6
12
2
Determine the c-chart two-sigma upper and lower control limits for this process. Is the process in statistical control?
A machine is used to fill cans of motor oil additive. A single sample can is selected every hour and the net
weight of the can is obtained. Since the filling process is automated, it has very stable variability, and long
experience indicates that s = 0.02 oz. The process target (process mean when in control) is 8.02 oz. A
tabular cusum is being used for this process with standardized values h=4.5 and k=0.5. If the values of
Cumulative sums at the end of measurement 7 were C,"
+
= 0.030 and C,¯ = 0.0 , and measurement 8 is
equal to Xg = 8.071, what will be the Cumulative sum at the end of measurement 8, that is C3
+
= ?
0.041
0.071
0.051
0.046
0.061
Auto pistons at Wemming Chung's plant in Shanghai are produced in a forging process, and the diameter is a critical factor that must be controlled. From sample
sizes of 10 pistons produced each day, the mean and the range of this diameter have been as follows:
a) What is the value of x?
=
x= 156.76 mm (round your response to two decimal places).
b) What is the value of R?
R= mm (round your response to two decimal places).
Day
1
2
3
4
5
Mean x
(mm)
158.9
155.2
155.6
157.5
156.6
Range R
(mm)
4.2
4.4
4.3
4.8
4.3
Chapter 12 Solutions
Production and Operations Analysis, Seventh Edition
Ch. 12.1 - Prob. 2PCh. 12.1 - Prob. 3PCh. 12.1 - Prob. 4PCh. 12.1 - Prob. 5PCh. 12.1 - Prob. 6PCh. 12.2 - Prob. 7PCh. 12.2 - Prob. 8PCh. 12.2 - Prob. 9PCh. 12.2 - Prob. 10PCh. 12.2 - Prob. 11P
Ch. 12.2 - Prob. 12PCh. 12.2 - Prob. 13PCh. 12.3 - Prob. 14PCh. 12.3 - Prob. 15PCh. 12.3 - Prob. 16PCh. 12.3 - Prob. 17PCh. 12.4 - Prob. 18PCh. 12.4 - Prob. 19PCh. 12.4 - Prob. 20PCh. 12.4 - Prob. 21PCh. 12.5 - Prob. 22PCh. 12.6 - Prob. 23PCh. 12.6 - Prob. 24PCh. 12.6 - Prob. 25PCh. 12.6 - Prob. 26PCh. 12.6 - Prob. 27PCh. 12.6 - Prob. 28PCh. 12.9 - Prob. 29PCh. 12.9 - Prob. 30PCh. 12.9 - Prob. 31PCh. 12.9 - Prob. 32PCh. 12.9 - Prob. 33PCh. 12.10 - Prob. 34PCh. 12.10 - Prob. 35PCh. 12.10 - Prob. 37PCh. 12.10 - Prob. 38PCh. 12.10 - Prob. 39PCh. 12.10 - Prob. 40PCh. 12.11 - Prob. 41PCh. 12.11 - Prob. 42PCh. 12.11 - Prob. 43PCh. 12.11 - Prob. 44PCh. 12.12 - Prob. 46PCh. 12.12 - Prob. 47PCh. 12.12 - Prob. 48PCh. 12 - Prob. 49APCh. 12 - Prob. 50APCh. 12 - Prob. 51APCh. 12 - Prob. 52APCh. 12 - Prob. 53APCh. 12 - Prob. 54APCh. 12 - Prob. 55APCh. 12 - Prob. 57APCh. 12 - Prob. 58APCh. 12 - Prob. 59APCh. 12 - Prob. 60APCh. 12 - Prob. 61APCh. 12 - Prob. 62APCh. 12 - Prob. 63APCh. 12 - Prob. 64APCh. 12 - Prob. 65APCh. 12 - Prob. 66APCh. 12 - Prob. 67APCh. 12 - Prob. 68APCh. 12 - Prob. 69APCh. 12 - Prob. 70AP
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