Probability and Statistics for Engineering and the Sciences
9th Edition
ISBN: 9781305251809
Author: Jay L. Devore
Publisher: Cengage Learning
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Chapter 9, Problem 77SE
Information about hand posture and forces generated by the fingers during manipulation of various daily objects is needed for designing high-tech hand prosthetic devices. The article “Grip Posture and Forces During Holding Cylindrical Objects with Circular Grips” (Ergonomics, 1996: 1163–1176) reported that for a sample of 11 females, the sample mean four-finger pinch strength (N) was 98.1 and the sample standard deviation was 14.2. For a sample of 15 males, the sample mean and sample standard deviation were 129.2 and 39.1, respectively.
a. A test carried out to see whether true average strengths for the two genders were different resulted in t = 2.51 and P - value = 019. Does the appropriate test procedure described in this chapter yield this value of t and the stated P-value?
b. Is there substantial evidence for concluding that true average strength for males exceeds that for females by more than 25 N? State and test the relevant hypotheses.
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Chapter 9 Solutions
Probability and Statistics for Engineering and the Sciences
Ch. 9.1 - An article in the November 1983 Consumer Reports...Ch. 9.1 - The National Health Statistics Reports dated Oct....Ch. 9.1 - Pilates is a popular set of exercises for the...Ch. 9.1 - Reliance on solid biomass fuel for cooking and...Ch. 9.1 - Persons having Reynauds syndrome are apt to suffer...Ch. 9.1 - An experiment to compare the tension bond strength...Ch. 9.1 - Is there any systematic tendency for part-time...Ch. 9.1 - Tensile-strength tests were carried out on two...Ch. 9.1 - The article Evaluation of a Ventilation Strategy...Ch. 9.1 - An experiment was performed to compare the...
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