Question 1

Which of the following variables would most likely follow a Normal model?
A) family income
B) scores on an easy test
C) heights of singers in a co-ed choir
D) all of these
E) weights of adult male elephants

Accepted Answer

E

Question 2

The standard deviation of the data displayed in this dotplot is most likely to be … 
A) 8.
B) 5.
C) 20.
D) 12.
E) 18.

Accepted Answer

D

Question 3

Which of these variables about German Shepherds is most likely to be described by a Normal
Model?
A) number of days housed
B) age
C) weight
D) breed
E) veterinary costs

Accepted Answer

Weight is a continuous variable that is often normally distributed in populations, making it suitable for a Normal Model.

Question 4

Suppose that a Normal model describes fuel economy (miles per gallon) for automobiles and that a Saturn has a standardized score (z $( \mathrm { z } - \mathrm { score } ) \text { of } + 2.2$ This means that Saturns . . .
A) get 2.2 mpg more than the average car.
B) achieve fuel economy that is 2.2 standard deviations better than the average car.
C) get 2.2 times the gas mileage of the average car.
D) get 2.2 miles per gallon.
E) have a standard deviation of 2.2 mpg.

Accepted Answer

A z-score of +2.2 indicates that the Saturn's fuel economy is 2.2 standard deviations above the average fuel economy.

Question 5

Which of these variables is most likely to follow a Normal model?
A) number of TV sets at home
B) hours of homework last week
C) number of cigarettes smoked daily
D) eye color
E) head circumference

Accepted Answer

Head circumference is a continuous variable that is likely to be normally distributed in a population, as many biological measurements tend to follow a normal distribution.

Question 6

Your Stats teacher tells you your test score was the 3rd quartile for the class. Which is true?
I. You got 75% on the test.
II. You can't really tell what this means without knowing the standard deviation.
III. You can't really tell what this means unless the class distribution is nearly Normal.
A) II only
B) I only
C) III only
D) none of these
E) II and III

Accepted Answer

The 3rd quartile means you scored higher than 75% of the class, but it doesn't specify the percentage score you received. It also doesn't require knowledge of the standard deviation or the distribution being nearly Normal to understand its meaning.

Question 7

Which of these variables is most likely to be bimodal?
A) number of cigarettes smoked daily
B) head circumference
C) number of TV sets at home
D) hours of homework last week
E) eye color

Accepted Answer

The answer of Which of these variables is most likely...

Question 8

The United States Census collects data on many variables about individuals and households.
Which variable is categorical?
A) hours worked per week
B) annual electricity cost
C) family size
D) type of residence
E) monthly mortgage

Accepted Answer

Type of residence is categorical because it describes a characteristic or quality that can be divided into categories, such as apartment, house, or condo, rather than a numerical value.

Question 9

Which is true of the data shown in the histogram?  I. The distribution is approximately symmetric.
II) The mean and median are approximately equal.
III) The median and IQR summarize the data better than the mean and standard deviation.
A) I and II
B) I, II, and III
C) I only
D) III only
E) I and III

Accepted Answer

The answer of Which is true of the data shown...

Question 10

The mean number of hours worked for the 30 males was 6, and for the 20 females was 9. The
Overall mean number of hours worked …
A) is 7.2
B) is none of these.
C) cannot be determined.
D) is 7.5
E) is 6.5

Accepted Answer

The overall mean number of hours worked can be calculated as the weighted average of the mean number of hours worked by males and females. The weight for males is 30/50 and the weight for females is 20/50. Therefore, the overall mean number of hours worked is (30/50) * 6 + (20/50) * 9 = 7.2.

Question 11

School administrators collect data on students attending the school. Which of the following
Variables is quantitative?
A) none of these
B) whether the student is in AP* classes
C) whether the student has taken the SAT
D) class (freshman, soph., junior, senior)
E) grade point average

Accepted Answer

Grade point average is a numerical value that can be measured and used for calculations, making it a quantitative variable.

Question 12

The average scores for Wisconsin schools on the ACT are summarized in the ogive shown. Estimate
The IQR of the average scores. 
A) 7
B) 50
C) 2.8
D) 6
E) 1.6

Accepted Answer

The answer of The average scores for Wisconsin schools on...

Question 13

The veterinary bills for the dogs are summarized in the ogive shown. Estimate the IQR of these
Expenses. 
A) $75
B) $50
C) $100
D) $150
E) $200

Accepted Answer

The answer of The veterinary bills for the dogs are...

Question 14

Environmental researchers have collected rain acidity data for several decades. They want to see if
There is any evidence that attempts to reduce industrial pollution have produced a trend toward
Less acidic rainfall. They should display their data in a(n)…
A) timeplot
B) contingency table
C) histogram
D) bar graph
E) boxplot

Accepted Answer

A timeplot is appropriate for displaying data collected over time to identify trends or patterns, such as changes in rain acidity due to reduced industrial pollution.

Question 15

A professor has kept records on grades that students have earned in his class. If he wants to
Examine the percentage of students earning the grades A, B, C, D, and F during the most recent
Term, which kind of plot could he make?
A) boxplot
B) timeplot
C) pie chart
D) dotplot
E) histogram

Accepted Answer

A pie chart is suitable for showing the percentage distribution of categorical data, such as grades.

Question 16

Which type of plot would be most appropriate to display the responses to type of residence?
A) pie chart
B) boxplot
C) histogram
D) timeplot
E) dotplot

Accepted Answer

A pie chart is most appropriate for displaying categorical data like types of residence, as it shows the proportion of each category in relation to the whole.

Question 17

Which type of plot would be least likely to reveal that a distribution is bimodal?
A) histogram
B) dotplot
C) ogive
D) boxplot
E) stemplot

Accepted Answer

A boxplot would not reveal that a distribution is bimodal because it only shows the median, quartiles, and outliers.

Question 18

Which of these variables is most likely to follow a Normal model for U.S. adults?
A) ACT scores
B) eye color
C) monthly mortgage
D) income
E) commuting time

Accepted Answer

ACT scores are designed to follow a normal distribution, as they are standardized test scores.

Question 19

The standard deviation of the data displayed in this dotplot is closest to… 
A) 2.
B) 4.
C) 1.
D) 3.5.
E) 0.5.

Accepted Answer

The answer of The standard deviation of the data displayed...

Question 20

Which of the following summaries are changed by adding a constant to each data value?
I. the mean
II. the median
III. the standard deviation
A) I, II, and III
B) I and II
C) I only
D) I and III
E) III only

Accepted Answer

Adding a constant to each data value affects the mean and the median by increasing them by that constant, but it does not affect the standard deviation, as standard deviation measures the spread of data, not its location.

Quiz 1: Exploring and Understanding Data

Which of the following variables would most likely follow a Normal model?

The standard deviation of the data displayed in this dotplot is most likely to be …

Which of these variables about German Shepherds is most likely to be described by a Normal Model?

Suppose that a Normal model describes fuel economy (miles per gallon) for automobiles and that a Saturn has a standardized score (z $( \mathrm { z } - \mathrm { score } ) \text { of } + 2.2$ This means that Saturns . . .

Which of these variables is most likely to follow a Normal model?

Your Stats teacher tells you your test score was the 3rd quartile for the class. Which is true? I. You got 75% on the test. II. You can't really tell what this means without knowing the standard deviation. III. You can't really tell what this means unless the class distribution is nearly Normal.

Which of these variables is most likely to be bimodal?

The United States Census collects data on many variables about individuals and households. Which variable is categorical?

Which is true of the data shown in the histogram? I. The distribution is approximately symmetric. II) The mean and median are approximately equal. III) The median and IQR summarize the data better than the mean and standard deviation.

The mean number of hours worked for the 30 males was 6, and for the 20 females was 9. The Overall mean number of hours worked …

School administrators collect data on students attending the school. Which of the following Variables is quantitative?

The average scores for Wisconsin schools on the ACT are summarized in the ogive shown. Estimate The IQR of the average scores.

The veterinary bills for the dogs are summarized in the ogive shown. Estimate the IQR of these Expenses.

Environmental researchers have collected rain acidity data for several decades. They want to see if There is any evidence that attempts to reduce industrial pollution have produced a trend toward Less acidic rainfall. They should display their data in a(n) …

A professor has kept records on grades that students have earned in his class. If he wants to Examine the percentage of students earning the grades A, B, C, D, and F during the most recent Term, which kind of plot could he make?

Which type of plot would be most appropriate to display the responses to type of residence?

Which type of plot would be least likely to reveal that a distribution is bimodal?

Which of these variables is most likely to follow a Normal model for U.S. adults?

The standard deviation of the data displayed in this dotplot is closest to…

Which of the following summaries are changed by adding a constant to each data value? I. the mean II. the median III. the standard deviation