WGU C207 DATA-DRIVEN DECISION MAKING OA PRACTICE
QUESTIONS, VERIFIED ANSWERS & RATIONALES 100% CORRECT!
(Descriptive vs Inferential Statistics)
Question 1 (Multiple Choice)
An operations manager calculates the mean, median, and standard deviation of last
month's delivery times for a complete census of all 500 completed shipments. What
branch of statistics is the manager using?
● A. Descriptive statistics
● B. Inferential statistics
● C. Non-parametric probability distribution modeling
● D. Predictive classification modeling
Correct Answer: A. Descriptive statistics
Rationale: Descriptive statistics involves organizing, summarizing, and presenting the
main features of a dataset (such as calculating metrics for an entire census population).
Question 2 (Multiple Choice)
A political analyst takes a random sample of 1,000 registered voters and uses the
sample results to estimate the proportion of the entire national voting population that
supports a specific legislative bill, establishing a 95% confidence interval. What branch
of statistics is being applied?
● A. Inferential statistics
● B. Descriptive statistics
● C. Historical data auditing
● D. Deterministic optimization
Correct Answer: A. Inferential statistics
Rationale: Inferential statistics uses data collected from a sample to make
generalizations, estimates, hypotheses tests, or predictions about a broader population.
Question 3 (Multiple Choice)
, A retail store manager creates a bar chart displaying the exact total monthly sales
revenue for each month of the previous fiscal year. What is the primary function of this
chart?
● A. To describe and summarize historical data visually.
● B. To test a hypothesis about future customer behavior with 99% confidence.
● C. To estimate population parameters from a sample subset.
● D. To eliminate all sampling error from upcoming audits.
Correct Answer: A. To describe and summarize historical data visually.
Rationale: Bar charts and historical revenue summaries fall under descriptive statistics
because they organize and display known data without generalizing beyond it.
Question 4 (Multiple Choice)
An HR director wants to test whether the average tenure of employees in the
engineering department is significantly different from the company-wide average, using
a sample of 45 engineers. What statistical tool is required?
● A. Inferential hypothesis testing (such as a t-test)
● B. Descriptive frequency tabulation
● C. A bar chart of total departmental headcount
● D. The calculation of the population mode
Correct Answer: A. Inferential hypothesis testing (such as a t-test)
Rationale: Hypothesis testing is a core component of inferential statistics, used to
determine whether sample data provides sufficient evidence to draw conclusions about
a population parameter.
Question 5 (Multiple Choice)
What is the fundamental distinction between a population parameter and a sample
statistic?
● A. A parameter describes a characteristic of an entire population, whereas a
statistic describes a characteristic of a sample drawn from that population.
● B. A parameter is calculated using descriptive graphs, while a statistic is
calculated using regression.
● C. Parameters are always subject to sampling error, whereas statistics are
always 100% error-free.
● D. Parameters only apply to qualitative nominal data.
QUESTIONS, VERIFIED ANSWERS & RATIONALES 100% CORRECT!
(Descriptive vs Inferential Statistics)
Question 1 (Multiple Choice)
An operations manager calculates the mean, median, and standard deviation of last
month's delivery times for a complete census of all 500 completed shipments. What
branch of statistics is the manager using?
● A. Descriptive statistics
● B. Inferential statistics
● C. Non-parametric probability distribution modeling
● D. Predictive classification modeling
Correct Answer: A. Descriptive statistics
Rationale: Descriptive statistics involves organizing, summarizing, and presenting the
main features of a dataset (such as calculating metrics for an entire census population).
Question 2 (Multiple Choice)
A political analyst takes a random sample of 1,000 registered voters and uses the
sample results to estimate the proportion of the entire national voting population that
supports a specific legislative bill, establishing a 95% confidence interval. What branch
of statistics is being applied?
● A. Inferential statistics
● B. Descriptive statistics
● C. Historical data auditing
● D. Deterministic optimization
Correct Answer: A. Inferential statistics
Rationale: Inferential statistics uses data collected from a sample to make
generalizations, estimates, hypotheses tests, or predictions about a broader population.
Question 3 (Multiple Choice)
, A retail store manager creates a bar chart displaying the exact total monthly sales
revenue for each month of the previous fiscal year. What is the primary function of this
chart?
● A. To describe and summarize historical data visually.
● B. To test a hypothesis about future customer behavior with 99% confidence.
● C. To estimate population parameters from a sample subset.
● D. To eliminate all sampling error from upcoming audits.
Correct Answer: A. To describe and summarize historical data visually.
Rationale: Bar charts and historical revenue summaries fall under descriptive statistics
because they organize and display known data without generalizing beyond it.
Question 4 (Multiple Choice)
An HR director wants to test whether the average tenure of employees in the
engineering department is significantly different from the company-wide average, using
a sample of 45 engineers. What statistical tool is required?
● A. Inferential hypothesis testing (such as a t-test)
● B. Descriptive frequency tabulation
● C. A bar chart of total departmental headcount
● D. The calculation of the population mode
Correct Answer: A. Inferential hypothesis testing (such as a t-test)
Rationale: Hypothesis testing is a core component of inferential statistics, used to
determine whether sample data provides sufficient evidence to draw conclusions about
a population parameter.
Question 5 (Multiple Choice)
What is the fundamental distinction between a population parameter and a sample
statistic?
● A. A parameter describes a characteristic of an entire population, whereas a
statistic describes a characteristic of a sample drawn from that population.
● B. A parameter is calculated using descriptive graphs, while a statistic is
calculated using regression.
● C. Parameters are always subject to sampling error, whereas statistics are
always 100% error-free.
● D. Parameters only apply to qualitative nominal data.
