TRY IT YOURSELF ANSWERS A37 Section 2.4 1. 35, or $35,000; The range of the starting salaries for Corporation B, which is $35,000, is much larger than the range of Corporation A. 2. s 2 = 110.3; s = 10.5, or $10,500 3. s2 ≈ 132.6; s ≈ 11.5 4. x ≈ 20.8; s ≈ 6.7 5. Sample answer: 7, 7, 7, 7, 7, 13, 13, 13, 13, 13 6. 34.13% 7. At least 75% of Iowa’s population is between 0 and 87.2 years old. Because 80 6 87.2, an age of 80 lies within two standard deviations of the mean. So, this age is not unusual. 8. x = 1.7; s ≈ 1.5 Both the mean and sample standard deviation decreased slightly. 9. x ≈ 157.0; s ≈ 147.1 Both the mean and sample standard deviation increased. 10. Los Angeles: CV ≈ 41.8% Dallas: CV ≈ 32.2% The office rentals are more variable in Los Angeles than in Dallas. Section 2.5 1. Q1 = 23, Q2 = 31, Q3 = 35 About one quarter of the winning scores were 23 points or less. About one half were 31 points or less, and about three quarters were 35 points or less. 2. Q1 = 27.5, Q2 = 35, Q3 = 51.5 About one quarter of these universities charge tuition of $27,500 or less, about one half charge $35,000 or less, and about three quarters charge $51,500 or less. 3. IQR = 12; 55 is an outlier. 4. 10 20 30 40 50 60 13 23 31 35 55 Points Scored by Winning Teams About 50% of the winning scores were between 23 and 35 points. About 25% of the winning scores were less than 23 points. About 25% of the winning scores were greater than 35 points. 5. 34; About 65% of the winning scores were 34 points or less. 6. 28th percentile 7. For $60, z = -1.25. For $71, z = 0.125. For $92, z = 2.75. 8. Man: z = -3.3; Woman: z ≈ -1.7 The z-score for the 5-foot-tall man is 3.3 standard deviations below the mean. This is a very unusual height for a man. The z-score for the 5-foot-tall woman is 1.7 standard deviations below the mean.This is among the typical heights for a woman. Chapter 3 Section 3.1 1. (1) M F M F M F No Not sure Yes 6 outcomes Let Y = Yes, N = No, NS = Not sure, M= Male, F = Female. Sample space = 5YM, YF, NM, NF, NSM, NSF6 (2) 35-49 18-34 50+ 35-49 18-34 50+ 35-49 18-34 50+ No Not sure Yes 9 outcomes Let Y = Yes, N = No, NS = Not sure, 50+ = 50 and older. Sample space = 5Y18–34, Y35–49, Y50+, N18–34, N35–49, N50+, NS18–34, NS35–49, NS50+6 (3) NESMWW NESMWW NESMWW No Not sure Yes 12 outcomes Let Y = Yes, N = No, NS = Not sure, NE = Northeast, S = South, MW= Midwest, W= West. Sample space = 5YNE, YS, YMW, YW, NNE, NS, NMW, NW, NSNE, NSS, NSMW, NSW6 2. (1) 6. Not a simple event because it is an event that consists of more than a single outcome. (2) 1. Simple event because it is an event that consists of a single outcome.
RkJQdWJsaXNoZXIy NjM5ODQ=