Question 1

Construct a pie chart representing the given data set.
-$\begin{array}{cc}
\hline \begin{array}{l}
\text { Computers } \
\text { per household }
\end{array} & \begin{array}{c}
\text { Number of } \
\text { households }
\end{array} \
\hline 0 & 72 \
1 & 128 \
2 & 76 \
3 & 36 \
\hline
\end{array}$

A)

B)

C)

D)

Accepted Answer

The answer of Construct a pie chart representing the given...

Question 2

The stack plot below shows the value of each of Danny's investments. The stack plot contains three regions. Theuppermost unshaded region represents the value of Danny's investment in individual stocks. The center shaded regionrepresents the value of Danny's investment in mutual funds and the bottom region in black represents the value ofDanny's investment in a CD. The thickness of a region at a particular time tells you its value at that time.  Use the graph to answer the question.
-In which year was the value of Danny's investment in individual stocks the highest?
A)year 4
B)year 0
C)year 5
D)year 8

Accepted Answer

The answer of The stack plot below shows the value...

Question 3

A statement is made about correlation. State whether the correlation is positive or negative and whether the correlation ismost likely due to coincidence, a common underlying cause, or a direct cause.
-Towns with a lot of churches had a lot of homicides last year. Towns with fewer churches had fewer homicides.
A)Positive correlation; direct cause
B)Negative correlation; common underlying cause
C)Positive correlation; common underlying cause
D)Positive correlation; coincidence

Accepted Answer

The statement indicates a positive correlation because both the number of churches and homicides increase together. It's most likely due to a common underlying cause, such as population size, rather than churches directly causing homicides.

Question 4

Construct a pie chart representing the given data set.
-$\begin{array}{l}
\text { Main form of exercise for employees of one company: }\
\begin{array}{lr}
\text { None: } & 30 \% \
\text { Walking: } & 18 \% \
\text { Running: } & 4 \% \
\text { Golf: } & 11 \% \
\text { Weight Training: } & 26 \% \
\text { Other: } & 11 \%
\end{array}
\end{array}$ 
A)

B)

C)

D)

Accepted Answer

The answer of Construct a pie chart representing the given...

Question 5

A sample statistic and margin of error are given. Find the confidence interval likely to contain the population parameterof interest and answer the question.
-A poll conducted the day before the student-body presidential election at a midwestern university showed that 53.0 percent favored Mario, the rest favoring Yin Ling. The margin of error was 5.0
Percentage points. Should Yin Ling have conceded the election?
A)48% to 53.0%; no
B)53.0% to 58%; yes
C)48% to 58%; no
D)50.5% to 55.5%; yes

Accepted Answer

The confidence interval is calculated by subtracting and adding the margin of error to the sample statistic. Therefore, 53.0% ± 5.0% gives a range of 48% to 58%. Since this range includes values both below and above 50%, it's not certain that Mario would win, so Yin Ling should not have conceded.

Question 6

Make a scatter diagram for the data.
-The following table gives the total sales (revenue)and profits for 8 retailers. $\begin{array}{lcc}
\hline \text { Company } & \begin{array}{c}
\text { Total Sales } \
\text { (Millions of \$) }
\end{array} & \begin{array}{c}
\text { Profits } \
\text { (Millions of \$) }
\end{array} \
\hline \text { Adams } & 9.5 & 0.5 \
\text { Browns } & 22.0 & 1.4 \
\text { Clay } & 35.0 & 1.8 \
\text { Donners } & 64.0 & 3.0 \
\text { Esters } & 27.5 & 0.9 \
\text { Framer } & 45.0 & 2.6 \
\text { Gillies } & 15.0 & 0.8 \
\text { Hays } & 57.0 & 2.2 \
\hline
\end{array}$

A)

B)

C)

D)

Accepted Answer

The answer of Make a scatter diagram for the data.
-The...

Question 7

Use the guidelines to evaluate the study. From the information given, what is the biggest flaw in the study?
-A medical researcher randomly selects 500 Japanese people and 500 Americans. She questions the 1000 people. She finds that the Americans work longer hours on average and also that the
Americans have a higher rate of heart disease. She concludes that working longer hours is
Associated with a higher incidence of heart disease.
A)Variables are hard to define/measure
B)Selection bias
C)The source
D)Participation bias
E)Confounding variables

Accepted Answer

The biggest flaw in the study is the presence of confounding variables. The study does not account for other factors that could influence the incidence of heart disease, such as diet, genetics, lifestyle, or healthcare access, which might differ significantly between the Japanese and American populations. These uncontrolled variables could confound the relationship between working hours and heart disease.

Question 8

Determine whether the study involves selection bias, participation bias, both selection bias and participation bias, orneither.
-You are interested in the degree of satisfaction amongst customers at your video store. For one week, you hand a customer satisfaction questionnaire to every customer who comes into the store
And ask them to fill it out and place it in a box after they check out.
A)Participation Bias
B)Participation Bias and Selection Bias
C)Selection Bias
D)No Bias

Accepted Answer

This study involves participation bias because not all customers who receive the questionnaire may choose to fill it out, leading to a situation where only those with strong opinions (either positive or negative) might participate, skewing the results.

Question 9

Identify which of these types of sampling is used: simple random, stratified, systematic, or convenience.
-49 students are selected at random from the Sophomore class, 39 from the Junior class, and 48 from the Senior classes.
A)Simple random
B)Convenience
C)Stratified
D)Systematic

Accepted Answer

This is an example of stratified sampling because the population is divided into subgroups (Sophomore, Junior, and Senior classes) and random samples are taken from each subgroup.

Question 10

The stack plot below shows the value of each of Danny's investments. The stack plot contains three regions. Theuppermost unshaded region represents the value of Danny's investment in individual stocks. The center shaded regionrepresents the value of Danny's investment in mutual funds and the bottom region in black represents the value ofDanny's investment in a CD. The thickness of a region at a particular time tells you its value at that time.  Use the graph to answer the question.
-In year 8, what was the approximate value of Danny's investment in mutual funds?
A)$6000
B)$2500
C)$1900
D)$4000

Accepted Answer

The question implies that Danny's investment grew over time, and by year 8, the value was approximately $4000.

Question 11

Use the guidelines to evaluate the study. From the information given, what is the biggest flaw in the study?
-You would like to know if the customers of your video store are satisfied. You hand a customer satisfaction questionnaire to every customer who comes into the store and ask them to fill it out
And place it in a box after they check out. The questionnaire asks customers to rate their satisfaction
On a scale of 1-10 with regard to the video selection and customer service.
A)Confounding variables
B)Setting may not encourage honest responses
C)Wording of the questions
D)Participation Bias
E)Selection Bias

Accepted Answer

EThe biggest flaw in this study is participation bias (D) and selection bias (E). Participation bias occurs because not all customers may choose to fill out the questionnaire, possibly leading to overrepresentation of certain opinions (e.g., those who had a particularly positive or negative experience). Selection bias (E) is present because the study only includes customers who come into the store, excluding potential dissatisfied customers who no longer visit or those who prefer online services, thus not accurately representing the entire customer base.

Question 12

A statement is made about correlation. State whether the correlation is positive or negative and whether the correlation ismost likely due to coincidence, a common underlying cause, or a direct cause.
-People who drive faster, cover the distance in a shorter time.
A)Positive correlation; direct cause
B)Negative correlation; common underlying cause
C)Positive correlation; common underlying cause
D)Negative correlation; direct cause

Accepted Answer

The correlation is negative because as driving speed increases, the time taken to cover a distance decreases. This is a direct cause because driving faster directly results in covering the distance in less time.

Question 13

Use the graph to answer the question.
- Identify the utility that makes up about 25% of the total bill in May.
A)Gas
B)Water
C)Electric
D)None of the utilities makes up 25% of the total bill in May

Accepted Answer

The answer of Use the graph to answer the question.
-...

Question 14

State whether you think that the variables have strong positive correlation, weak positive correlation, strong negativecorrelation, weak negative correlation, or no correlation.
-Number of appliances sold and revenue of appliance store
A)No correlation
B)Weak positive correlation
C)Weak negative correlation
D)Strong positive correlation
E)Strong negative correlation

Accepted Answer

The number of appliances sold and the revenue of an appliance store are likely to have a strong positive correlation because as more appliances are sold, the revenue of the store is expected to increase.

Question 15

State whether the scatter diagram shows strong positive correlation, weak positive correlation, strong negativecorrelation, weak negative correlation, or no correlation.
-
A)Weak positive correlation
B)Strong positive correlation
C)No correlation
D)Strong negative correlation
E)Weak negative correlation

Accepted Answer

The answer of State whether the scatter diagram shows strong...

Question 16

Answer the question.
-What name is given to a statistical graph where each category has its own wedge and the wedges are displayed on top of one another?
A)Multiple bar graph
B)Pictograph
C)Stack plot
D)Contour map

Accepted Answer

A stack plot (or stacked plot) visualizes data in a way where parts of the data are stacked on top of each other, representing the whole as segments of a single wedge for each category. This is commonly used to show how individual parts contribute to an aggregate total over time or across categories.

Question 17

Use the guidelines to evaluate the study. From the information given, what is the biggest flaw in the study?
-An educational researcher wishes to compare the effectiveness of two different math textbooks. She has the tenth graders at one school use the first book for one year and the tenth graders at another
School use the second textbook for one year. At the end of the year, she gives the same math test to
Both classes and compares the results.
A)The setting
B)Selection bias
C)Participation bias
D)The source
E)Confounding variables

Accepted Answer

The biggest flaw is the presence of confounding variables, as the study does not account for differences between the two schools that could affect the results, such as teaching quality, student demographics, or school resources.

Question 18

The stack plot below shows the value of each of Danny's investments. The stack plot contains three regions. Theuppermost unshaded region represents the value of Danny's investment in individual stocks. The center shaded regionrepresents the value of Danny's investment in mutual funds and the bottom region in black represents the value ofDanny's investment in a CD. The thickness of a region at a particular time tells you its value at that time.  Use the graph to answer the question.
-In which year was the value of Danny's investment in individual stocks the least?
A)year 1
B)year 8
C)year 7
D)year 0

Accepted Answer

The answer of The stack plot below shows the value...

Question 19

Identify which of these types of sampling is used: simple random, stratified, systematic, or convenience.
-A market researcher selects 500 people from each of 10 cities.
A)Convenience
B)Stratified
C)Simple random
D)Systematic

Accepted Answer

The market researcher is using stratified sampling by dividing the population into subgroups (cities) and then taking a sample from each subgroup.

Question 20

Construct a pie chart representing the given data set.
-Intended major of high school students:
$\begin{array}{lr}
\text { Science: } & 32 \% \
\text { Social Science: } & 8 \% \
\text { Humanities: } & 20 \% \
\text { Business: } & 16 \% \
\text { Other: } & 24 \%
\end{array}$

A)

B)

C)

D)

Accepted Answer

The answer of Construct a pie chart representing the given...

Quiz 5: Statistical Reasoning

Identify which of these types of sampling is used: simple random, stratified, systematic, or convenience. -49 students are selected at random from the Sophomore class, 39 from the Junior class, and 48 from the Senior classes.

A statement is made about correlation. State whether the correlation is positive or negative and whether the correlation ismost likely due to coincidence, a common underlying cause, or a direct cause. -People who drive faster, cover the distance in a shorter time.

Use the graph to answer the question. - Identify the utility that makes up about 25% of the total bill in May.

State whether you think that the variables have strong positive correlation, weak positive correlation, strong negativecorrelation, weak negative correlation, or no correlation. -Number of appliances sold and revenue of appliance store

State whether the scatter diagram shows strong positive correlation, weak positive correlation, strong negativecorrelation, weak negative correlation, or no correlation. -

Answer the question. -What name is given to a statistical graph where each category has its own wedge and the wedges are displayed on top of one another?

Identify which of these types of sampling is used: simple random, stratified, systematic, or convenience. -A market researcher selects 500 people from each of 10 cities.