Student Solutions Manual for Devore's Probability and Statistics for Engineering and the Sciences, 9th
9th Edition
ISBN: 9798214004020
Author: Jay L. Devore
Publisher: Cengage Learning US
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Chapter 9, Problem 83SE
In an experiment to compare bearing strengths of pegs inserted in two different types of mounts, a sample of 14 observations on stress limit for red oak mounts resulted in a sample mean and sample standard deviation of 8.48 MPa and .79 MPa, respectively, whereas a sample of 12 observations when Douglas fir mounts were used gave a mean of 9.36 and a standard deviation of 1.52 (“Bearing Strength of White Oak Pegs in Red Oak and Douglas Fir Timbers,” J. of Testing and Evaluation, 1998, 109–114). Consider testing whether or not true average stress limits are identical for the two types of mounts. Compare df’s and P-values for the unpooled and pooled t tests.
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Chapter 9 Solutions
Student Solutions Manual for Devore's Probability and Statistics for Engineering and the Sciences, 9th
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