Introduction to Statistical Quality Control
7th Edition
ISBN: 9781118146811
Author: Montgomery, Douglas C.
Publisher: John Wiley & Sons Inc
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Textbook Question
Chapter 4, Problem 16E
Two machines are used for filling glass bottles with a soft-drink beverage. The filling processes have known standard deviations al σ1 = 0.010 liter and σ2 = 0.015 liter, respectively. A random sample of n1 = 25 bottles from machine 1 and n2 = 20 bottles from machine 2 results in average net contents of
- (a) Test the hypothesis that both machines fill to the same net contents, using α = 0.05. What are your conclusions?
- (b) Find the P-value for this test.
- (c) Construct a 95% confidence interval on the difference in
mean fill volume.
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Chapter 4 Solutions
Introduction to Statistical Quality Control
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