Statistics for Engineers and Scientists
4th Edition
ISBN: 9780073401331
Author: William Navidi Prof.
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 6.6, Problem 1E
Two extrusion machines that manufacture steel rods are being compared. In a sample of 1000 rods taken from machine 1, 960 met specifications regarding length and diameter. In a sample of 600 rods taken from machine 2,582 met the specifications. Machine 2 is more expensive to run, so it is decided that machine 1 will be used unless it can be convincingly shown that machine 2 produces a larger proportion of rods meeting specifications.
- a. State the appropriate null and alternate hypotheses for making the decision as to which machine to use.
- b. Compute the P-value.
- c. Which machine should be used?
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(c) Answer the obstetrician's question at the a= 0.05 level of significance using a z-test for a population proportion. State the null and alternative hypotheses for this
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Ho: p
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%D
H1: p
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Use technology to compute the P-value for this test. Use the Tech Help button for further assistance.
P-value =D
(Round to three decimal places as needed.)
Chapter 6 Solutions
Statistics for Engineers and Scientists
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