The Statistical Sleuth (3rd Edition, 2012) –
Solutions Manual – Ramsey & Schafer
Height, in meters, in measured for each person in a sample. After the data are collected, all the
height measurements are converted from meters to centimeters by multiplying each
measurement by 100. Which of the following statistics will remain the same for both units of
measure?
A. the mean of the height measurements
B. the median of the height measurements
C. the standard deviation of the height measurements
D. the maximum of the height measurements
E. the z-scores of the height measurements - answers-E
a school principal wanted to investigate student opinion about the food served in the school
cafeteria. the principal selected at random samples of 50 first-year students, 50 second-year
students, 50 third-year students, and 50 fourth-year students to complete a questionnaire.
Which of the following best describes the principal's sampling plan?
A. a stratified random sample
B. a simple random sample
C. a cluster sample
D. a convenience sample
E. a systematic sample - answers-A
a candy company produces individually wrapped candies. The quality control manager for the
company believes that the weight of the candies is approximately normally distributed with
mean 720 milligrams (mg). If the manager's belief is correct, which of the following intervals of
weights will contain the largest proportion of the candies in the distribution of weights?
1
, A. 740 mg to 780 mg
B. 700 mg to 740 mg
C. 680 mg to 720 mg
D. 660 mg to 700 mg
E. 620 mg to 660 mg - answers-B
a company currently uses Brand A lightbulbs, which have a mean life of 1,000 hours. a
salesperson marketing Brand B, a new brand of bulb, contacts the company. the company will
switch to the new brand of bulb only if there is convincing evidence that the mean life of Brand
B is greater than 1,000 hours. What should the hypotheses for the company test be? - answers-
Ho: the mean life of Brand B is 1,000 hours
Ha: the mean life of Brand B bulbs is more than 1,000 hours
a graph (not shown) of the selling prices of homes in a certain city for the month of April reveals
that the distribution is skewed to the left. Which of the following statements is the most
reasonable conclusion about the selling prices based on the graph?
A. the mean is greater than the median
B. the median is the average of the first quartile and the third quartile
C. there are fewer selling prices between the first quartile and the median than there are
between the median and the third quartile
D. there are more selling prices that are less than the mean than selling prices that are greater
than the mean
E. the value of maximum minus third quartile is less than the value of first quartile minus
minimum - answers-E
a survey was conducted in which both men and women were asked a question about current
issue. possible responses to this question were "in favor of", "not in favor of" "no opinion". A
chi-square test is to be used to determine whether the response to this question is independent
of gender. the number of degrees of freedom for the chi-square test in this situation is
2
Solutions Manual – Ramsey & Schafer
Height, in meters, in measured for each person in a sample. After the data are collected, all the
height measurements are converted from meters to centimeters by multiplying each
measurement by 100. Which of the following statistics will remain the same for both units of
measure?
A. the mean of the height measurements
B. the median of the height measurements
C. the standard deviation of the height measurements
D. the maximum of the height measurements
E. the z-scores of the height measurements - answers-E
a school principal wanted to investigate student opinion about the food served in the school
cafeteria. the principal selected at random samples of 50 first-year students, 50 second-year
students, 50 third-year students, and 50 fourth-year students to complete a questionnaire.
Which of the following best describes the principal's sampling plan?
A. a stratified random sample
B. a simple random sample
C. a cluster sample
D. a convenience sample
E. a systematic sample - answers-A
a candy company produces individually wrapped candies. The quality control manager for the
company believes that the weight of the candies is approximately normally distributed with
mean 720 milligrams (mg). If the manager's belief is correct, which of the following intervals of
weights will contain the largest proportion of the candies in the distribution of weights?
1
, A. 740 mg to 780 mg
B. 700 mg to 740 mg
C. 680 mg to 720 mg
D. 660 mg to 700 mg
E. 620 mg to 660 mg - answers-B
a company currently uses Brand A lightbulbs, which have a mean life of 1,000 hours. a
salesperson marketing Brand B, a new brand of bulb, contacts the company. the company will
switch to the new brand of bulb only if there is convincing evidence that the mean life of Brand
B is greater than 1,000 hours. What should the hypotheses for the company test be? - answers-
Ho: the mean life of Brand B is 1,000 hours
Ha: the mean life of Brand B bulbs is more than 1,000 hours
a graph (not shown) of the selling prices of homes in a certain city for the month of April reveals
that the distribution is skewed to the left. Which of the following statements is the most
reasonable conclusion about the selling prices based on the graph?
A. the mean is greater than the median
B. the median is the average of the first quartile and the third quartile
C. there are fewer selling prices between the first quartile and the median than there are
between the median and the third quartile
D. there are more selling prices that are less than the mean than selling prices that are greater
than the mean
E. the value of maximum minus third quartile is less than the value of first quartile minus
minimum - answers-E
a survey was conducted in which both men and women were asked a question about current
issue. possible responses to this question were "in favor of", "not in favor of" "no opinion". A
chi-square test is to be used to determine whether the response to this question is independent
of gender. the number of degrees of freedom for the chi-square test in this situation is
2
