A66 ODD ANSWERS 5. a 6. d 7. c 8. b 9. The probability of getting fewer than 25 successes; P1x 6 24.52 11. The probability of getting exactly 33 successes; P132.5 6 x 6 33.52 13. The probability of getting at most 150 successes; P1x 6 150.52 15. Binomial: P15 … x … 72 ≈ 0.549 Normal: P14.5 6 x 6 7.52 = 0.5463 (Tech: 0.5466) The results are about the same. 17. Cannot use normal distribution because np 6 5 19. Can use normal distribution (a) 0.1308 (Tech: 0.1291) x = 24.5 x x = 25.5 Number of college students μ= 24.8 σ= 3.07 15 19 23 27 31 35 (b) 0.0630 (Tech: 0.0629) x x = 29.5 Number of college students μ= 24.8 σ= 3.07 15 19 23 27 31 35 (c) 0.4602 (Tech: 0.4611) x x = 24.5 Number of college students μ= 24.8 σ= 3.07 15 19 23 27 31 35 21. Can use normal distribution (a) 0.0649 x = 50.5 x Number of adults μ= 43 σ= 4.95 31 34 37 40 43 46 49 52 55 (b) 0.9351 x = 50.5 x Number of adults μ= 43 σ= 4.95 31 34 37 40 43 46 49 52 55 (c) 0.4544 (Tech: 0.4534) x = 45.5 x = 39.5 x Number of adults μ= 43 σ= 4.95 31 34 37 40 43 46 49 52 55 23. Cannot use normal distribution nq 6 5 (a) 0.0737 (b) 0.7870 (c) 0.7509 25. Can use normal distribution (a) 0.9370 (Tech: 0.9373) x Number of adults μ= 38 x = 29.5 σ= 5.55 26 29 32 35 38 41 44 47 50 (b) 0.3264 (Tech: 0.3261) x Number of adults μ= 38 x = 40.5 σ= 5.55 26 29 32 35 38 41 44 47 50 (c) 0.6472 (Tech: 0.6477) x Number of adults μ= 38 x = 45.5 x = 34.5 σ= 5.55 26 29 32 35 38 41 44 47 50 27. (a) 0.0098 (b) 0.7794 (Tech: 0.7805) (c) 1 29. Highly unlikely. Answers will vary. 31. 0.1020 Uses and Abuses for Chapter 5 (page 284) 1. (a) Not unusual. A sample mean of 112 is less than 2 standard deviations from the population mean. (b) Unusual. A sample mean of 105 is more than 2 standard deviations from the population mean. 2. The ages of students at a high school may not be normally distributed. 3. Answers will vary. Review Exercises for Chapter 5 (page 286) 1. m = 15, s = 3 3. Curve B has the greatest mean because its line of symmetry occurs the farthest to the right. 5. 0.6772 7. 0.6293 9. 0.7157 11. 0.00235 (Tech: 0.00236) 13. 0.4495 15. 0.4365 (Tech: 0.4364) 17. 0.1336
RkJQdWJsaXNoZXIy NjM5ODQ=