Probability and Statistics for Engineering and the Sciences
9th Edition
ISBN: 9781305251809
Author: Jay L. Devore
Publisher: Cengage Learning
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Textbook Question
Chapter 9.3, Problem 46E
Example 7.11 gave data on the modulus of elasticity obtained 1 minute after loading in a certain configuration. The cited article also gave the values of modulus of elasticity obtained 4 weeks after loading for the same lumber specimens. The data is presented here.
| Observation | 1 min | 4 weeks | Dift'erence |
| 1 | 10.490 | 9,110 | 1380 |
| 2 | 16,620 | 13,250 | 3370 |
| 3 | 17,300 | 14.720 | 2580 |
| 4 | 15.480 | 12.740 | 2740 |
| 5 | 12,970 | 10,120 | 2850 |
| 6 | 17,260 | 14.570 | 2690 |
| 7 | 13,400 | 11,220 | 2180 |
| 8 | 13,900 | 11.100 | 2800 |
| 9 | 13,630 | 11,420 | 2210 |
| 10 | 13,260 | 10,910 | 2350 |
| 11 | 14,370 | 12,110 | 2260 |
| 12 | 11,700 | 8,620 | 3080 |
| 13 | 15.470 | 12,590 | 2880 |
| 14 | 17.840 | 15.090 | 2750 |
| 15 | 14.070 | 10,550 | 3520 |
| 16 | 14.760 | 12,230 | 2530 |
Calculate and interpret an upper confidence bound for the true average difference between 1-minute modulus and 4-week modulus; first check the plausibility of any necessary assumptions
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Chapter 9 Solutions
Probability and Statistics for Engineering and the Sciences
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