A First Course in Probability (10th Edition)
10th Edition
ISBN: 9780134753119
Author: Sheldon Ross
Publisher: PEARSON
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Kevlar epoxy is a material used on the NASA space shuttles. Strands of this epoxy were tested at the 90% breaking strength. The following data represent time to failure (in hours) for a random sample of 50 epoxy strands. Let x be a random variable representing time to failure (in hours) at 90% breaking strength.
| 0.54 | 1.80 | 1.52 | 2.05 | 1.03 | 1.18 | 0.80 | 1.33 | 1.29 | 1.14 |
| 3.34 | 1.54 | 0.08 | 0.12 | 0.60 | 0.72 | 0.92 | 1.05 | 1.43 | 3.02 |
| 1.81 | 2.17 | 0.63 | 0.56 | 0.03 | 0.09 | 0.18 | 0.34 | 1.51 | 1.45 |
| 1.52 | 0.19 | 1.55 | 0.02 | 0.07 | 0.65 | 0.40 | 0.24 | 1.51 | 1.45 |
| 1.60 | 1.80 | 4.69 | 0.08 | 7.89 | 1.58 | 1.63 | 0.03 | 0.23 | 0.72 |
(a) Find the range.
(b) Use a calculator to calculate Σx and Σx2.
(c) Use the results of part (b) to compute the samplemean , variance, and standard deviation for the time to failure. (Round your answers to four decimal places.)
(b) Use a calculator to calculate Σx and Σx2.
| Σx | = |
| Σx2 | = |
(c) Use the results of part (b) to compute the sample
| x | = |
| s2 | = |
| s | = |
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