Introduction to Statistical Quality Control
7th Edition
ISBN: 9781118146811
Author: Montgomery, Douglas C.
Publisher: John Wiley & Sons Inc
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Chapter 4, Problem 8E
The tensile strength of a fiber used in manufacturing cloth is of interest to the purchaser. Previous experience indicates that the standard deviation of tensile strength is 2 psi. A random sample of eight fiber specimens is selected, and the average tensile strength is found to be 127 psi.
- (a) Test the hypothesis that the
mean tensile strength equals 125 psi versus the alternative that the mean exceeds 125 psi. Use - (b) What is the P-value for this test?
- (c) Discuss why a one-sided alternative was chosen in part (a).
- (d) Construct a 95% lower confidence interval on the mean tensile strength.
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Chapter 4 Solutions
Introduction to Statistical Quality Control
Ch. 4 - Suppose that you are testing the following...Ch. 4 - Suppose that you are testing the following...Ch. 4 - Suppose that you are testing the following...Ch. 4 - Suppose that you are testing the following...Ch. 4 - Suppose that you are testing the following...Ch. 4 - Suppose that you are testing the following...Ch. 4 - The inside diameters of bearings used in an...Ch. 4 - The tensile strength of a fiber used in...Ch. 4 - The service life of a battery used in a cardiac...Ch. 4 - Using the data from Exercise 4.7, construct a 95%...
Ch. 4 - A new process has been developed for applying...Ch. 4 - A machine is used to fill containers with a liquid...Ch. 4 - Ferric chloride is used as a flux in some types of...Ch. 4 - The diameters of aluminum alloy rods produced on...Ch. 4 - The output voltage of a power supply is assumed to...Ch. 4 - Two machines are used for filling glass bottles...Ch. 4 - Two quality control technicians measured the...Ch. 4 - Suppose that x1N(,12) and x2N(2,22), and that x1...Ch. 4 - Two different hardening processes(1) saltwater...Ch. 4 - A random sample of 200 printed circuit boards...Ch. 4 - A random sample of 500 connecting rod pins...Ch. 4 - Two processes are used to produce forgings used in...Ch. 4 - A new purification unit is installed in a chemical...Ch. 4 - Two different types of glass bottles are suitable...Ch. 4 - The diameter of a metal rod is measured by 12...Ch. 4 - The cooling system in a nuclear submarine consists...Ch. 4 - An experiment was conducted to investigate the...Ch. 4 - Suppose we wish to test the hypotheses H0:=15H1:15...Ch. 4 - Consider the hypotheses H0:=0H1:0 where 2 is...Ch. 4 - Sample size allocation. Suppose we are testing the...Ch. 4 - Develop a test for the hypotheses H0: 1 = 2 H1: 1 ...Ch. 4 - Nonconformities occur in glass bottles according...Ch. 4 - An inspector counts the surface-finish defects in...Ch. 4 - An in-line tester is used to evaluate the...Ch. 4 - An article in Solid State Technology (May 1987)...Ch. 4 - Compare the mean etch uniformity values at each of...Ch. 4 - An article in the ACI Materials Journal (Vol. 84,...Ch. 4 - Compare the mean compressive strength at each...Ch. 4 - An aluminum producer manufactures carbon anodes...Ch. 4 - Plot the residuals from Exercise 4.36 against the...Ch. 4 - An article in Environmental International (Vol....Ch. 4 - An article in the Journal of the Electrochemical...Ch. 4 - The tensile strength of a paper product is related...Ch. 4 - A plant distills liquid air to produce oxygen,...Ch. 4 - Plot the residuals from Exercise 4.43 and comment...Ch. 4 - Plot the residuals from Exercise 4.44 and comment...Ch. 4 - The brake horsepower developed by an automobile...Ch. 4 - Analyze the residuals from the regression model in...Ch. 4 - Table 4E.11 contains the data from a patient...Ch. 4 - Analyze the residuals from the regression model on...Ch. 4 - Reconsider the patient satisfaction data in Table...Ch. 4 - Analyze the residuals from the multiple regression...Ch. 4 - Consider the Minitab output below. (a) Fill in the...Ch. 4 - Suppose that you are testing H0: 1 = 2 versus H1: ...Ch. 4 - Suppose that you are testing H0: = 2 versus H1: ...Ch. 4 - Consider the Minitab output below. (a) Fill in the...Ch. 4 - Consider the Minitab output shown below. (a) Is...Ch. 4 - Consider the Minitab output shown below. (a) Fill...Ch. 4 - Consider the Minitab output below. (a) Fill in the...Ch. 4 - Consider a one-way or single-factor ANOVA with...Ch. 4 - Consider the Minitab ANOVA output below. Fill in...
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