Question 1

Data on the amount of money made in a year by 1,000 families in a small town were collected.You want to know if the money made is normally distributed.Which of the following would you use?
A)Bar chart
B)Scatter plot
C)Boxplot
D)Time-series plot

Accepted Answer

A boxplot would be the best option to determine if the data is normally distributed. It shows the distribution of the data by plotting the median, quartiles, and outliers. If the box is symmetrical and the whiskers are similar in length, the data is likely to be normally distributed. A bar chart shows frequencies or counts for categorical data, a scatter plot shows the relationship between two continuous variables, and a time-series plot shows a pattern of data over time.

Question 2

An insurance company evaluates many variables about a person before deciding on an appropriate rate for automobile insurance.A representative from a local insurance agency selected a random sample of 100 insured drivers and recorded X,the amount of claims each made in the last 3 years.A Pareto chart can be used to present this information.

Accepted Answer

False

Question 3

The owner of a local nightclub has recently surveyed a random sample of n = 250 customers of the club.She would now like to determine whether or not the mean age of her customers is more than 30.If so,she plans to alter the entertainment to appeal to an older crowd.If not,no entertainment changes will be made.Which of the following tests will you perform to help her make a decision?
A)t test for the mean
B)Z test for the proportion
C)Pooled-variance t test
D)Separate-variance t test

Accepted Answer

The owner is trying to determine if the mean age of her customers is more than 30, and she has a sample size of 250 customers. Since we are dealing with a continuous variable (age) and the sample size is relatively large (n = 250), we can use a t test for the mean. The null hypothesis would be that the mean age is equal to 30, and the alternative hypothesis would be that the mean age is greater than 30. By conducting this test, the owner can determine whether or not to make changes to the entertainment to appeal to an older crowd.

Question 4

The opinions (classified as "for," "neutral" or "against")of a sample of 200 people broken down by gender about the latest congressional plan to eliminate anti-trust exemptions for professional baseball.You can present this information using a scatter plot.

Accepted Answer

A scatter plot is not the appropriate type of graph to display the opinions of a sample of people about a political issue. A bar graph or pie chart would be more appropriate.

Question 5

Every spring semester,the School of Business coordinates a luncheon for graduating seniors,their families,and friends with local business leaders.Corporate sponsorship pays for the lunches of each of the seniors,but students have to purchase tickets to cover the cost of lunches served to guests they bring with them.Data on the number of guests each graduating senior invited to the luncheon and the number of graduating seniors in each category were collected.A histogram can be used to present this information.

Accepted Answer

A histogram is a useful tool for showing the distribution of numerical data, and can be used to present the information about the number of guests invited by graduating seniors and the number of graduating seniors in each category.

Question 6

Data on the amount of time spent studying and the exam score of 150 students at a high school were collected.You want to know if a student's exam score is linearly related to the amount of time spent on studying.Which of the following would you compute?
A)Arithmetic mean
B)Median
C)Coefficient of variation
D)Coefficient of correlation

Accepted Answer

The coefficient of correlation measures the strength and direction of the linear relationship between two variables, in this case, the amount of time spent studying and the exam score. Therefore, it would be the best choice to determine if there is a linear relationship between the two variables.

Question 7

Data on the amount of money made in a year by 1,000 families in a small town were collected.You want to know the difference in the amount of money made in that year by the middle 50% of the 1,000 families.Which of the following would you compute?
A)Arithmetic mean
B)Median
C)Interquartile range
D)Coefficient of correlation

Accepted Answer

The interquartile range (IQR) represents the middle 50% of the data, making it the best choice for this problem as we want to know the difference in the amount of money made by the middle 50% of families. The arithmetic mean and coefficient of correlation are not relevant for this problem, and while the median is a measure of central tendency, it doesn't indicate the range of the middle 50% of the data.

Question 8

A sample of 200 students at a Big-Ten university was taken after the midterm to ask whether they went bar hopping the weekend before the midterm or spent the weekend studying,and whether they did well or poorly on the midterm.You can use a contingency table to present this information.

Accepted Answer

A contingency table is a useful tool for organizing and presenting data on two categorical variables, which is exactly what is being analyzed in this scenario.

Question 9

A sample of 100 fuses from a very large shipment is found to have 10 that are defective.Based on this information,which of the following will you construct to learn about the proportion of fuses that are defective?
A)Confidence interval estimate for the total using the Student's t distribution
B)Confidence interval estimate for the mean using the Student's t distribution
C)Confidence interval estimate for the proportion using the standard normal distribution
D)Confidence interval estimate for the difference between two means using the standard normal distribution

Accepted Answer

Since we are interested in finding the proportion of defective fuses, which is a proportion, we need to construct a confidence interval estimate for the proportion. For this, we can use the standard normal distribution as the sample size is large enough (n=100) and the proportion of defective fuses (p=0.1) is not too small or large.

Question 10

At a meeting of information systems officers for regional offices of a national company,a survey was taken to determine the number of employees the officers supervise in the operation of their departments,where X is the number of employees overseen by each information systems officer.A stem-and-leaf display can be used to present this information.

Accepted Answer

A stem-and-leaf display is a useful tool for organizing and presenting numerical data, particularly when the data set is relatively small. In this case, the data being collected (the number of employees overseen by each information systems officer) would be well-suited for a stem-and-leaf display.

Question 11

An insurance company evaluates many variables about a person before deciding on an appropriate rate for automobile insurance.A representative from a local insurance agency selected a random sample of 15 insured drivers and recorded the amount of claims each made in the last 3 years.Based on this information,which of the following will you construct to learn about the mean amount of claims made by the company's customer?
A)Confidence interval estimate for the mean using the standard normal distribution
B)Confidence interval estimate for the mean using the Student's t distribution
C)Confidence interval estimate for the proportion using the standard normal distribution
D)Confidence interval estimate for the difference between two means using the standard normal distribution

Accepted Answer

Since the sample size is small (n=15) and the population standard deviation is unknown, a confidence interval estimate for the mean using the Student's t distribution would be appropriate. The other options are not relevant to the given scenario.

Question 12

A professor of economics at a small Texas university wanted to determine what year in school students were taking his tough economics course.Data were collected on the class status ("freshman," "sophomore," "junior" or "senior")of 50 students enrolled in one of his economics course.A side-by-side bar chart can be used to present this information.

Accepted Answer

The answer of A professor of economics at a small...

Question 13

Data on the amount of money made in a year by 1,000 families in a small town were collected.You want to know how much each family will get if the money made by all the 1,000 families is pooled together and then evenly redistributed back to them.Which of the following would you compute?
A)Arithmetic mean
B)Median
C)Interquartile range
D)Coefficient of correlation

Accepted Answer

To evenly redistribute the money back to the families, we would need to calculate the total amount of money made by all 1,000 families and divide by 1,000. This is the definition of the arithmetic mean. The median, interquartile range, and coefficient of correlation are not relevant to this question.

Question 14

Every spring semester,the School of Business coordinates with local business leaders a luncheon for graduating seniors,their families,and friends.Corporate sponsorship pays for the lunches of each of the seniors,but students have to purchase tickets to cover the cost of lunches served to guests they bring with them.Data on the number of guests each graduating senior invited to the luncheon and the number of graduating seniors in each category were collected.You want to know the most popular number of guests brought by the graduating seniors.Which of the following will you compute?
A)Arithmetic mean
B)Median
C)Interquartile range
D)Mode

Accepted Answer

To determine the most popular number of guests brought by graduating seniors, we need to compute the mode, which is the value that appears most frequently in the data set. The mode will give us the number of guests that a majority of graduating seniors invited to the luncheon.

Question 15

Data were collected on the amount of detergent used in gallons in a month by 25 drive-through car wash operations in Phoenix.You can use a time-series plot to present this information.

Accepted Answer

A time-series plot is used to display data over time, but the information given does not have any indication of time (such as monthly or yearly data). Therefore, a time-series plot would not be the appropriate way to present this information.

Question 16

A survey claims that 9 out of 10 doctors recommend aspirin for their patients with headaches.To test this claim,a random sample of 100 doctors results in 83 who indicate that they recommend aspirin.Which of the following tests will you perform?
A)t test for the mean
B)Z test for the proportion
C)Pooled-variance t test
D)Separate-variance t test

Accepted Answer

Since we are testing a proportion (9 out of 10 doctors), we will use the Z test for proportion. Also, since our sample size is sufficiently large (n = 100), we do not need to worry about applying the central limit theorem. Therefore, the best choice for this scenario is the Z test for proportion.

Question 17

A survey was conducted to determine how people rated the quality of programming available on television.Respondents were asked to rate the overall quality from 0 (no quality at all)to 100 (extremely good quality).A cumulative percentage polygon (ogive)can be used to present this information.

Accepted Answer

A cumulative percentage polygon (ogive) can indeed be used to present this information as it shows the cumulative frequency distribution of the ratings, which is related to the overall quality.

Question 18

Private colleges and universities rely on money contributed by individuals and corporations for their operating expenses.Much of this money is put into a fund called an endowment,and the college spends only the interest earned by the fund.A recent survey of 8 private colleges in the United States collected information on the endowment amount.Based on this information,which of the following will you construct to learn about the mean endowment of all private colleges in the United States?
A)Confidence interval estimate for the total using the Student's t distribution
B)Confidence interval estimate for the mean using the Student's t distribution
C)Confidence interval estimate for the proportion using the standard normal distribution
D)Confidence interval estimate for the difference between two means using the standard normal distribution

Accepted Answer

The question asks specifically about learning about the mean endowment of all private colleges in the United States. Therefore, a confidence interval estimate for the mean using the Student's t distribution is the best choice. Options A and D involve comparing means or totals, which are not relevant here. Option C involves a proportion, which is not relevant to the question.

Question 19

Every spring semester,the School of Business coordinates with local business leaders a luncheon for graduating seniors,their families,and friends.Corporate sponsorship pays for the lunches of each of the seniors,but students have to purchase tickets to cover the cost of lunches served to guests they bring with them.Data on the number of guests each graduating senior invited to the luncheon from 500 graduating seniors last year were collected.Based on this information,which of the following will you construct to learn about the percentage of seniors who will bring at least one guest to a luncheon?
A)Confidence interval estimate for the total using the Student's t distribution
B)Confidence interval estimate for the mean using the Student's t distribution
C)Confidence interval estimate for the proportion using the standard normal distribution
D)Confidence interval estimate for the difference between two means using the standard normal distribution

Accepted Answer

We are interested in the percentage of seniors who will bring at least one guest to the luncheon, which is a proportion. Therefore, we need to construct a confidence interval estimate for the proportion using the standard normal distribution.

Question 20

Data on the amount of time spent studying for a particular exam at a high school were collected for 150 students.You want to know at least how much time half of the students spent studying for that exam.Which of the following would you compute?
A)Arithmetic mean
B)Median
C)Coefficient of variation
D)Coefficient of correlation

Accepted Answer

The median is the best choice for this situation because it is the exact midpoint of the data set when the data is arranged in numerical order. In other words, half of the students spent more time studying than the median and half spent less time studying than the median. The arithmetic mean could also be computed, but it might not accurately represent the typical amount of time spent studying if there are outliers (students who spent significantly more or less time studying than the majority). The coefficient of variation and coefficient of correlation are not relevant for this situation.

Quiz 18: A Roadmap for Analyzing Data

Data on the amount of money made in a year by 1,000 families in a small town were collected.You want to know if the money made is normally distributed.Which of the following would you use?

The opinions (classified as "for," "neutral" or "against")of a sample of 200 people broken down by gender about the latest congressional plan to eliminate anti-trust exemptions for professional baseball.You can present this information using a scatter plot.

Data on the amount of time spent studying and the exam score of 150 students at a high school were collected.You want to know if a student's exam score is linearly related to the amount of time spent on studying.Which of the following would you compute?

Data on the amount of money made in a year by 1,000 families in a small town were collected.You want to know the difference in the amount of money made in that year by the middle 50% of the 1,000 families.Which of the following would you compute?

A sample of 200 students at a Big-Ten university was taken after the midterm to ask whether they went bar hopping the weekend before the midterm or spent the weekend studying,and whether they did well or poorly on the midterm.You can use a contingency table to present this information.

A sample of 100 fuses from a very large shipment is found to have 10 that are defective.Based on this information,which of the following will you construct to learn about the proportion of fuses that are defective?

Data on the amount of money made in a year by 1,000 families in a small town were collected.You want to know how much each family will get if the money made by all the 1,000 families is pooled together and then evenly redistributed back to them.Which of the following would you compute?

Data were collected on the amount of detergent used in gallons in a month by 25 drive-through car wash operations in Phoenix.You can use a time-series plot to present this information.

A survey claims that 9 out of 10 doctors recommend aspirin for their patients with headaches.To test this claim,a random sample of 100 doctors results in 83 who indicate that they recommend aspirin.Which of the following tests will you perform?

A survey was conducted to determine how people rated the quality of programming available on television.Respondents were asked to rate the overall quality from 0 (no quality at all)to 100 (extremely good quality).A cumulative percentage polygon (ogive)can be used to present this information.

Data on the amount of time spent studying for a particular exam at a high school were collected for 150 students.You want to know at least how much time half of the students spent studying for that exam.Which of the following would you compute?