Multiple Choice Review Chapters 5 and 6
1) The heights of adult women are approximately normally distributed about a mean of 65 inches, with a standard deviation of 2 inches. If Rachel is at the 99th percentile in height for adult women, then her height, in inches, is closest to 60 B) 62 C) 68 E) 74 D) 70
Which of the following is the best estimate of the standard deviation of the distribution shown in the figure? A) 5 C) 30 D) 50 E) 60 B) 10
A company wanted to determine the health care costs of its employees A company wanted to determine the health care costs of its employees. A sample of 25 employees were interviewed and their medical expenses for the previous year were determined. Later the company discovered that the highest medical expense in the sample was mistakenly recorded as 10 times the actual amount. However, after correcting the error, the correct amount was still greater than or equal to any other medical expense in the sample. Which of the following sample statistics must have remained the same after the correction was made? A) Mean C) Mode D) Range E) Variance B) Median
Suppose that the distribution of a set of scores has a mean of 47 and a standard deviation of 14. If 4 is added to each score, what will be the mean and the standard deviation of the distribution of new scores? Mean Standard Deviation (B) 51 18 (C) 47 14 (D) 47 16 (E) 47 18 (A) 51 14
5) “Normal” body temperature varies by time of day 5) “Normal” body temperature varies by time of day. A series of readings was taken of the body temperature of a subject. The mean reading was found to be 36.5 C with a standard deviation of 0.3C. When converted to F, the mean and standard deviation are …. [F = C(1.8) + 32] 97.7, 32 B) 97.7, 0.30 D) 97.7, 0.97 E) 97.7, 1.80 C) 97.7, 0.54
Vanessa is enrolled in a very large college calculus class Vanessa is enrolled in a very large college calculus class. On the first exam, the class mean was 75 and the standard deviation was 10. On the second exam, the class mean was 70 and the standard deviation was 15. Vanessa scored 85 on both exams. Assuming the scores on each exam were approximately normally distributed, on which exam did Vanessa score better relative to the rest of the class? It is impossible to tell because the class size is not given. B) It is impossible to tell because the correlation between the two sets of exams is not given. C) She scored much better on the first exam. D) She scored much better on the second exam. E) She scored about equally well on both exams.
7) The boxplots summarize two data sets, A and B 7) The boxplots summarize two data sets, A and B. Which of the following must be true? A) Set A contains more data than Set B. B) The box of Set A contains more data than the box of Set B. D) The data in Set A have a smaller interquartile range than the data in Set B. E) The minimum and maximum in Set A are larger than the minimum and maximum in Set B. C) The data in Set A have a larger range than the data in Set B.
The weights of men are approximately normally distributed The weights of men are approximately normally distributed. The coach of a football team monitors each team players weight through out the season. This week, the z-score of weight for a member of the football team is 1.25. Which of the following is a correct interpretation of this z-score? This week the member weighs 1.25 lb. more than last week. (B) This week the member weighs 1.25 lb. less than last week. (C) This week the member weighs 1.25 lb. more than the average football player on this team. (D) This week the member weighs 1.25 standard deviations more than the he did last week. (E) This week the member weighs 1.25 standard deviations more than the average football player on this team.
9) For a given school year, a reporter has been told that the average teacher’s salary was $59,500 with a standard deviation of $17,200. The reporter also knows that teachers will be receiving raises of 3.25% for the next school year. What would the reporter write for the new average teacher’s salary and standard deviation?
a) What proportion of the condos have a value of less than $90,000? 10) Prices of condominiums in a certain city are distributed approximately normal with a mean value of about $100,000 and a standard deviation of $10,000. a) What proportion of the condos have a value of less than $90,000? The proportion of condos with a value of less than $90,000 is 0.16. b) The middle 95% of the condo prices lie between what two values? The middle 95% of the condo prices lie between $80,000 and $120,000
Calculate boundaries (fences) and then graph a box plot given: Mean = 100.2 Median = 98 STDev = 15.83 Min = 40 Max = 200 Q1 = 60 Q3 = 115
. 40 200 60 98 115 -22.5 197.5
Given: N(9490, 100) What percent of student income is more than $9600?
Z = x - µ σ 9600-9490 100 = 1.1 From table .8643 Complement = 1-.8643 = .1357 9490 9590 9690
D 2) B 3) B 4) A 5) C 6) E 7) C 8) E