WGU C207 DATA-DRIVEN DECISION MAKING OA PRACTICE
QUESTIONS, VERIFIED ANSWERS & RATIONALES 100%
CORRECT!(Data Visualization & Interpretation)
Question 1 (Multiple Choice)
An operations manager at a manufacturing plant wants to display the frequency
distribution of continuous part lengths (measured in millimeters) to see if they follow a
normal bell curve. Which chart or graph type is most appropriate?
● A. Pie chart
● B. Histogram
● C. Pareto chart
● D. Scatter plot
Correct Answer: B. Histogram
Rationale: A histogram is specifically designed to display the frequency distribution of
continuous numerical data grouped into consecutive numerical bins (intervals). This
makes it the ideal tool for checking whether a continuous process measurement
approximates a normal distribution.
Question 2 (Multiple Choice)
A quality control supervisor wants to prioritize which types of customer complaints
(shipping delays, billing errors, damaged items, wrong sizes) to address first based on
the "80/20 rule." Which graphical tool should the supervisor use?
● A. Pareto chart
● B. Time-series line graph
● C. Box plot
● D. Scatter plot
Correct Answer: A. Pareto chart
Rationale: A Pareto chart combines a bar graph (showing frequencies of categorical
defects in descending order) with a cumulative line graph. It is used in Six Sigma and
quality management to identify the vital few categories that account for the majority of
problems (the 80/20 rule).
Question 3 (Multiple Choice)
, An analyst wants to visualize the relationship and check for correlation between two
continuous variables: employee daily hours of training ($x$) and units assembled per
hour ($y$). Which chart type is best suited for this objective?
● A. Bar chart
● B. Scatter plot
● C. Histogram
● D. Pie chart
Correct Answer: B. Scatter plot
Rationale: A scatter plot displays data points on a horizontal and vertical axis to
evaluate the relationship, direction, strength, and potential correlation between two
continuous numerical variables.
Question 4 (Multiple Choice)
A financial analyst reviews a box plot showing monthly operational expenses across
several regional offices. The box plot displays a median line inside the box, the
interquartile range (IQR) as the box itself, and a single data point plotted far above the
upper whisker. How should this single point be interpreted?
● A. A standard error calculation
● B. An outlier indicating an unusually high monthly expense anomaly
● C. A normal data point representing the mean
● D. A cumulative frequency total
Correct Answer: B. An outlier indicating an unusually high monthly expense anomaly
Rationale: In a box plot, values that fall significantly outside the upper or lower whiskers
(typically defined as more than $1.5 \times IQR$ above the third quartile or below the
first quartile) are plotted individually as points and represent statistical outliers.
Question 5 (Multiple Choice)
A retail store manager wants to compare total annual sales revenue across four distinct
product categories (Electronics, Apparel, Home Goods, Groceries). Which visualization
tool is most appropriate for comparing discrete categorical categories?
● A. Histogram
● B. Bar chart
● C. Scatter plot
● D. Pareto cumulative line
QUESTIONS, VERIFIED ANSWERS & RATIONALES 100%
CORRECT!(Data Visualization & Interpretation)
Question 1 (Multiple Choice)
An operations manager at a manufacturing plant wants to display the frequency
distribution of continuous part lengths (measured in millimeters) to see if they follow a
normal bell curve. Which chart or graph type is most appropriate?
● A. Pie chart
● B. Histogram
● C. Pareto chart
● D. Scatter plot
Correct Answer: B. Histogram
Rationale: A histogram is specifically designed to display the frequency distribution of
continuous numerical data grouped into consecutive numerical bins (intervals). This
makes it the ideal tool for checking whether a continuous process measurement
approximates a normal distribution.
Question 2 (Multiple Choice)
A quality control supervisor wants to prioritize which types of customer complaints
(shipping delays, billing errors, damaged items, wrong sizes) to address first based on
the "80/20 rule." Which graphical tool should the supervisor use?
● A. Pareto chart
● B. Time-series line graph
● C. Box plot
● D. Scatter plot
Correct Answer: A. Pareto chart
Rationale: A Pareto chart combines a bar graph (showing frequencies of categorical
defects in descending order) with a cumulative line graph. It is used in Six Sigma and
quality management to identify the vital few categories that account for the majority of
problems (the 80/20 rule).
Question 3 (Multiple Choice)
, An analyst wants to visualize the relationship and check for correlation between two
continuous variables: employee daily hours of training ($x$) and units assembled per
hour ($y$). Which chart type is best suited for this objective?
● A. Bar chart
● B. Scatter plot
● C. Histogram
● D. Pie chart
Correct Answer: B. Scatter plot
Rationale: A scatter plot displays data points on a horizontal and vertical axis to
evaluate the relationship, direction, strength, and potential correlation between two
continuous numerical variables.
Question 4 (Multiple Choice)
A financial analyst reviews a box plot showing monthly operational expenses across
several regional offices. The box plot displays a median line inside the box, the
interquartile range (IQR) as the box itself, and a single data point plotted far above the
upper whisker. How should this single point be interpreted?
● A. A standard error calculation
● B. An outlier indicating an unusually high monthly expense anomaly
● C. A normal data point representing the mean
● D. A cumulative frequency total
Correct Answer: B. An outlier indicating an unusually high monthly expense anomaly
Rationale: In a box plot, values that fall significantly outside the upper or lower whiskers
(typically defined as more than $1.5 \times IQR$ above the third quartile or below the
first quartile) are plotted individually as points and represent statistical outliers.
Question 5 (Multiple Choice)
A retail store manager wants to compare total annual sales revenue across four distinct
product categories (Electronics, Apparel, Home Goods, Groceries). Which visualization
tool is most appropriate for comparing discrete categorical categories?
● A. Histogram
● B. Bar chart
● C. Scatter plot
● D. Pareto cumulative line
