WGU C784 APPLIED HEALTHCARE
STATISTICS LATEST UPDATES 2026|2027| A
COMPREHENSIVE REVIEW OF 100
PRACTICE QUESTIONS WITH ANSWERS
RATIONALE| PASS GUARANTEED
Introduction
This comprehensive practice exam contains 100 unique, non-duplicated
questions designed to prepare you for the WGU C784 Applied Healthcare
Statistics Objective Assessment (OA). The questions cover all seven core
competencies:
1. Basic Numeracy & Calculation Skills (Questions 1-15)
2. Fractions, Decimals & Percentages (Questions 16-30)
3. Basic Algebra (Questions 31-45)
4. Descriptive Statistics for a Single Variable (Questions 46-65)
5. Descriptive Statistics for Two Variables (Questions 66-80)
6. Correlation & Regression (Questions 81-90)
7. Probability (Questions 91-100)
Questions 1-20: Mixed Foundational Concepts
1. A nurse records the following patient temperatures in Celsius: 36.5, 37.2,
38.1, 36.8, and 37.5. What is the mean temperature?
,A) 36.8°C
B) 37.2°C
C) 37.4°C
D) 37.0°C
Answer: B
Rationale: The mean is calculated by summing all values and dividing by the
number of values: (36.5 + 37.2 + 38.1 + 36.8 + 37.5) ÷ 5 = 186.1 ÷ 5 = 37.22°C,
which rounds to 37.2°C. Option A represents the lowest value, not the mean.
Option C is incorrect because it overestimates the central value. Option D is
incorrect because it does not accurately reflect the calculated average.
2. Convert the fraction 3/8 to a decimal.
A) 0.375
B) 0.38
C) 0.34
D) 0.40
Answer: A
Rationale: To convert 3/8 to a decimal, divide 3 by 8: 3 ÷ 8 = 0.375. Option B is a
rounded approximation but not the exact value. Option C is incorrect because 3/8
does not equal 0.34. Option D is incorrect as 3/8 is less than 0.40.
3. A hospital reports that 15% of patients admitted to the ICU develop an
infection. If 240 patients were admitted, how many developed an infection?
A) 24
B) 36
C) 48
D) 30
Answer: B
Rationale: To find 15% of 240, multiply 240 × 0.15 = 36. Option A represents
10% of 240. Option C represents 20% of 240. Option D represents 12.5% of 240,
not 15%.
,4. Solve for x: 3x + 7 = 22
A) x = 3
B) x = 5
C) x = 7
D) x = 9
Answer: B
Rationale: Subtract 7 from both sides: 3x = 15. Then divide by 3: x = 5. Option A
would give 3(3) + 7 = 16, not 22. Option C would give 3(7) + 7 = 28. Option D
would give 3(9) + 7 = 34.
5. Which measure of central tendency is most affected by extreme outliers?
A) Median
B) Mode
C) Mean
D) Range
Answer: C
Rationale: The mean is calculated using all values, so extreme outliers pull it
significantly in their direction. Option A (median) is resistant to outliers because it
depends only on position. Option B (mode) is the most frequent value and is
unaffected by outliers. Option D (range) is a measure of dispersion, not central
tendency, and while affected by outliers, the question specifically asks about
central tendency.
6. A dataset has a standard deviation of 0. What does this indicate?
A) The data is normally distributed
B) All values in the dataset are identical
C) The mean is zero
D) The data has extreme variability
, Answer: B
Rationale: Standard deviation measures the spread of data around the mean. A
standard deviation of 0 means there is no spread, indicating all values are exactly
the same. Option A is incorrect because normal distribution requires a positive
standard deviation. Option C confuses standard deviation with the mean value.
Option D is the opposite of what a zero standard deviation represents.
7. In a normal distribution, approximately what percentage of data falls
within two standard deviations of the mean?
A) 68%
B) 75%
C) 95%
D) 99.7%
Answer: C
Rationale: According to the Empirical Rule, approximately 95% of data falls
within two standard deviations of the mean in a normal distribution. Option A
represents one standard deviation. Option B is not a standard value in the
Empirical Rule. Option D represents three standard deviations.
8. A p-value of 0.03 is obtained from a hypothesis test with α = 0.05. What is
the correct conclusion?
A) Fail to reject the null hypothesis
B) Reject the null hypothesis
C) Accept the alternative hypothesis as proven
D) Increase the sample size
Answer: B
Rationale: When the p-value (0.03) is less than the significance level (0.05), we
reject the null hypothesis. Option A is incorrect because failing to reject would
require p > 0.05. Option C is incorrect because hypothesis tests do not "prove"
anything; they provide evidence. Option D is not a conclusion of the test itself.
STATISTICS LATEST UPDATES 2026|2027| A
COMPREHENSIVE REVIEW OF 100
PRACTICE QUESTIONS WITH ANSWERS
RATIONALE| PASS GUARANTEED
Introduction
This comprehensive practice exam contains 100 unique, non-duplicated
questions designed to prepare you for the WGU C784 Applied Healthcare
Statistics Objective Assessment (OA). The questions cover all seven core
competencies:
1. Basic Numeracy & Calculation Skills (Questions 1-15)
2. Fractions, Decimals & Percentages (Questions 16-30)
3. Basic Algebra (Questions 31-45)
4. Descriptive Statistics for a Single Variable (Questions 46-65)
5. Descriptive Statistics for Two Variables (Questions 66-80)
6. Correlation & Regression (Questions 81-90)
7. Probability (Questions 91-100)
Questions 1-20: Mixed Foundational Concepts
1. A nurse records the following patient temperatures in Celsius: 36.5, 37.2,
38.1, 36.8, and 37.5. What is the mean temperature?
,A) 36.8°C
B) 37.2°C
C) 37.4°C
D) 37.0°C
Answer: B
Rationale: The mean is calculated by summing all values and dividing by the
number of values: (36.5 + 37.2 + 38.1 + 36.8 + 37.5) ÷ 5 = 186.1 ÷ 5 = 37.22°C,
which rounds to 37.2°C. Option A represents the lowest value, not the mean.
Option C is incorrect because it overestimates the central value. Option D is
incorrect because it does not accurately reflect the calculated average.
2. Convert the fraction 3/8 to a decimal.
A) 0.375
B) 0.38
C) 0.34
D) 0.40
Answer: A
Rationale: To convert 3/8 to a decimal, divide 3 by 8: 3 ÷ 8 = 0.375. Option B is a
rounded approximation but not the exact value. Option C is incorrect because 3/8
does not equal 0.34. Option D is incorrect as 3/8 is less than 0.40.
3. A hospital reports that 15% of patients admitted to the ICU develop an
infection. If 240 patients were admitted, how many developed an infection?
A) 24
B) 36
C) 48
D) 30
Answer: B
Rationale: To find 15% of 240, multiply 240 × 0.15 = 36. Option A represents
10% of 240. Option C represents 20% of 240. Option D represents 12.5% of 240,
not 15%.
,4. Solve for x: 3x + 7 = 22
A) x = 3
B) x = 5
C) x = 7
D) x = 9
Answer: B
Rationale: Subtract 7 from both sides: 3x = 15. Then divide by 3: x = 5. Option A
would give 3(3) + 7 = 16, not 22. Option C would give 3(7) + 7 = 28. Option D
would give 3(9) + 7 = 34.
5. Which measure of central tendency is most affected by extreme outliers?
A) Median
B) Mode
C) Mean
D) Range
Answer: C
Rationale: The mean is calculated using all values, so extreme outliers pull it
significantly in their direction. Option A (median) is resistant to outliers because it
depends only on position. Option B (mode) is the most frequent value and is
unaffected by outliers. Option D (range) is a measure of dispersion, not central
tendency, and while affected by outliers, the question specifically asks about
central tendency.
6. A dataset has a standard deviation of 0. What does this indicate?
A) The data is normally distributed
B) All values in the dataset are identical
C) The mean is zero
D) The data has extreme variability
, Answer: B
Rationale: Standard deviation measures the spread of data around the mean. A
standard deviation of 0 means there is no spread, indicating all values are exactly
the same. Option A is incorrect because normal distribution requires a positive
standard deviation. Option C confuses standard deviation with the mean value.
Option D is the opposite of what a zero standard deviation represents.
7. In a normal distribution, approximately what percentage of data falls
within two standard deviations of the mean?
A) 68%
B) 75%
C) 95%
D) 99.7%
Answer: C
Rationale: According to the Empirical Rule, approximately 95% of data falls
within two standard deviations of the mean in a normal distribution. Option A
represents one standard deviation. Option B is not a standard value in the
Empirical Rule. Option D represents three standard deviations.
8. A p-value of 0.03 is obtained from a hypothesis test with α = 0.05. What is
the correct conclusion?
A) Fail to reject the null hypothesis
B) Reject the null hypothesis
C) Accept the alternative hypothesis as proven
D) Increase the sample size
Answer: B
Rationale: When the p-value (0.03) is less than the significance level (0.05), we
reject the null hypothesis. Option A is incorrect because failing to reject would
require p > 0.05. Option C is incorrect because hypothesis tests do not "prove"
anything; they provide evidence. Option D is not a conclusion of the test itself.
