WGU C784 Applied Healthcare Statistics
Pre-Assessment Exam Actual 2026/2027 with Detailed
Rationales | 100% Verified | Pass Guaranteed – A+
Graded
SECTION 1: DESCRIPTIVE STATISTICS & DATA VISUALIZATION (14
Questions)
Q1: A hospital administrator collects data on patient wait times (in minutes): 12, 15,
18, 20, 22, 25, 120. Which measure of central tendency is most appropriate for
describing typical wait time?
A. Mean
B. Median [CORRECT]
C. Mode
D. Range
Correct Answer: B
Rationale: The value 120 is an extreme outlier that would severely inflate the mean;
the median (20 minutes) represents the typical wait time without being skewed by
unusual extreme values.
Q2: Which measure of dispersion represents the average distance of each data point
from the mean?
A. Range
B. Interquartile range
C. Standard deviation [CORRECT]
D. Variance
Correct Answer: C
Rationale: Standard deviation is the square root of variance and represents the
average distance of data points from the mean in the original units of measurement,
making it the most interpretable measure of spread.
,Q3: A dataset of patient ages has a mean of 45 years and a standard deviation of 12
years. What is the coefficient of variation?
A. 0.27
B. 26.7% [CORRECT]
C. 57 years
D. 3.75%
Correct Answer: B
Rationale: The coefficient of variation is calculated as (standard deviation / mean) ×
100 = () × 100 = 26.7%, expressing relative variability as a percentage
independent of measurement units.
Q4: Which graphical representation is most appropriate for displaying the
distribution of a continuous variable and identifying skewness?
A. Bar chart
B. Pie chart
C. Histogram [CORRECT]
D. Scatterplot
Correct Answer: C
Rationale: A histogram displays the frequency distribution of continuous data by
grouping values into bins, revealing the shape, center, spread, and skewness of the
distribution.
Q5: In a box plot, which component represents the middle 50% of the data?
A. The whiskers
B. The interquartile range (the box) [CORRECT]
C. The median line
D. The outliers
Correct Answer: B
Rationale: The box in a box plot spans from the first quartile (Q1, 25th percentile) to
the third quartile (Q3, 75th percentile), representing the interquartile range that
contains the middle 50% of observations.
Q6: A frequency distribution of blood pressure readings shows a long tail extending
to the right. How is this distribution described?
A. Symmetric
B. Left-skewed (negatively skewed)
C. Right-skewed (positively skewed) [CORRECT]
D. Bimodal
Correct Answer: C
, Rationale: A right-skewed distribution has a long tail extending toward higher values
(to the right), with the mean typically greater than the median; common in healthcare
data such as hospital length of stay and costs.
Q7: Which measure of central tendency is calculated by identifying the most
frequently occurring value in a dataset?
A. Mean
B. Median
C. Mode [CORRECT]
D. Midrange
Correct Answer: C
Rationale: The mode is the value that appears most frequently in a dataset; it is the
only measure of central tendency applicable to nominal data and can identify the
most common category or value.
Q8: A nurse researcher reports that patient satisfaction scores have a standard
deviation of 0. What can be concluded?
A. The data contains outliers
B. All patients gave the same satisfaction score [CORRECT]
C. The mean is equal to the median
D. The sample size is very large
Correct Answer: B
Rationale: A standard deviation of zero indicates no variability—all data points are
identical, meaning every patient gave exactly the same satisfaction score.
Q9: Which graphical display uses vertical bars to show the frequency of categorical
data?
A. Histogram
B. Bar chart [CORRECT]
C. Box plot
D. Stem-and-leaf plot
Correct Answer: B
Rationale: A bar chart uses separated vertical bars to display frequencies or
proportions of categorical variables, with bar height representing the count or
percentage in each category.
Pre-Assessment Exam Actual 2026/2027 with Detailed
Rationales | 100% Verified | Pass Guaranteed – A+
Graded
SECTION 1: DESCRIPTIVE STATISTICS & DATA VISUALIZATION (14
Questions)
Q1: A hospital administrator collects data on patient wait times (in minutes): 12, 15,
18, 20, 22, 25, 120. Which measure of central tendency is most appropriate for
describing typical wait time?
A. Mean
B. Median [CORRECT]
C. Mode
D. Range
Correct Answer: B
Rationale: The value 120 is an extreme outlier that would severely inflate the mean;
the median (20 minutes) represents the typical wait time without being skewed by
unusual extreme values.
Q2: Which measure of dispersion represents the average distance of each data point
from the mean?
A. Range
B. Interquartile range
C. Standard deviation [CORRECT]
D. Variance
Correct Answer: C
Rationale: Standard deviation is the square root of variance and represents the
average distance of data points from the mean in the original units of measurement,
making it the most interpretable measure of spread.
,Q3: A dataset of patient ages has a mean of 45 years and a standard deviation of 12
years. What is the coefficient of variation?
A. 0.27
B. 26.7% [CORRECT]
C. 57 years
D. 3.75%
Correct Answer: B
Rationale: The coefficient of variation is calculated as (standard deviation / mean) ×
100 = () × 100 = 26.7%, expressing relative variability as a percentage
independent of measurement units.
Q4: Which graphical representation is most appropriate for displaying the
distribution of a continuous variable and identifying skewness?
A. Bar chart
B. Pie chart
C. Histogram [CORRECT]
D. Scatterplot
Correct Answer: C
Rationale: A histogram displays the frequency distribution of continuous data by
grouping values into bins, revealing the shape, center, spread, and skewness of the
distribution.
Q5: In a box plot, which component represents the middle 50% of the data?
A. The whiskers
B. The interquartile range (the box) [CORRECT]
C. The median line
D. The outliers
Correct Answer: B
Rationale: The box in a box plot spans from the first quartile (Q1, 25th percentile) to
the third quartile (Q3, 75th percentile), representing the interquartile range that
contains the middle 50% of observations.
Q6: A frequency distribution of blood pressure readings shows a long tail extending
to the right. How is this distribution described?
A. Symmetric
B. Left-skewed (negatively skewed)
C. Right-skewed (positively skewed) [CORRECT]
D. Bimodal
Correct Answer: C
, Rationale: A right-skewed distribution has a long tail extending toward higher values
(to the right), with the mean typically greater than the median; common in healthcare
data such as hospital length of stay and costs.
Q7: Which measure of central tendency is calculated by identifying the most
frequently occurring value in a dataset?
A. Mean
B. Median
C. Mode [CORRECT]
D. Midrange
Correct Answer: C
Rationale: The mode is the value that appears most frequently in a dataset; it is the
only measure of central tendency applicable to nominal data and can identify the
most common category or value.
Q8: A nurse researcher reports that patient satisfaction scores have a standard
deviation of 0. What can be concluded?
A. The data contains outliers
B. All patients gave the same satisfaction score [CORRECT]
C. The mean is equal to the median
D. The sample size is very large
Correct Answer: B
Rationale: A standard deviation of zero indicates no variability—all data points are
identical, meaning every patient gave exactly the same satisfaction score.
Q9: Which graphical display uses vertical bars to show the frequency of categorical
data?
A. Histogram
B. Bar chart [CORRECT]
C. Box plot
D. Stem-and-leaf plot
Correct Answer: B
Rationale: A bar chart uses separated vertical bars to display frequencies or
proportions of categorical variables, with bar height representing the count or
percentage in each category.
