Bundle: Probability and Statistics for Engineering and the Sciences, Loose-leaf Version, 9th + WebAssign Printed Access Card, Multi-Term Courses
9th Edition
ISBN: 9780357099797
Author: DEVORE, Jay L.
Publisher: Cengage Learning
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Chapter 1, Problem 64SE
Fretting is a wear process that results from tangential oscillatory movements of small amplitude in machine parts. The article “Grease effect on Fretting Wear of Mild Steel” (Industrial Lubrication and Tribology, 2008: 67-78) included the following data on volume wear (10−4mm3) for base oils having four different viscosities.
| Viscosity | Wear | |||||
| 20.4 | 58.8 | 30.8 | 27.3 | 29.9 | 17.7 | 76.5 |
| 30.2 | 44.5 | 47.1 | 48.7 | 41.6 | 32.8 | 18.3 |
| 89.4 | 73.3 | 57.1 | 66.0 | 93.8 | 133.2 | 81.1 |
| 252.6 | 30.6 | 24.2 | 16.6 | 38.9 | 28.7 | 23.6 |
- a. The sample coefficient of variation 100s/
- b. Construct a comparative boxplot of the data and comment on interesting features.
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Chapter 1 Solutions
Bundle: Probability and Statistics for Engineering and the Sciences, Loose-leaf Version, 9th + WebAssign Printed Access Card, Multi-Term Courses
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