WGU C955 PROBABILITY AND STATISTICS
OBJECTIVE ASSESSMENT EXAM (2026 /
2027) WITH QUESTIONS AND REVISED
ANSWERS, 100% GUARANTEE PASS
(UPDATED)
Core Domains:
• Descriptive Statistics (Measures of Center, Spread, and Graphical
Displays)
• Probability Rules, Counting Principles, and Distributions
• Inferential Statistics (Hypothesis Testing, Confidence Intervals, and
Sampling)
• Data Types and Study Design (Observational vs. Experimental)
• Correlation, Regression, and Bivariate Data
• Normal and Binomial Distributions
• Basic Numeracy and Algebraic Foundations
• Statistical Decision-Making and Interpretation
Introduction:
This comprehensive objective assessment is designed to evaluate the
student's mastery of applied probability and statistical concepts as outlined
in the WGU C955 curriculum. The examination covers a wide range of
topics including descriptive statistics, probability theory, inferential
statistics, and data interpretation. The format includes multiple-choice
questions that test both foundational knowledge and applied analytical
skills. Each question is accompanied by a verified answer and a detailed
rationale to reinforce understanding and promote conceptual clarity. This
,resource is aligned with the latest 2026/2027 course objectives and is
designed to prepare students for success on the official WGU C955
Objective Assessment exam.
SECTION ONE: QUESTIONS 1-200
1. A data set contains the values: 3, 5, 7, 9, 11. What is the mean of
this data set?
A. 5
B. 7
C. 8
D. 9
E. 10
Correct answer: B
RATIONALE: The mean is calculated by summing all values and
dividing by the number of observations. (3 + 5 + 7 + 9 + 11) / 5 =
= 7. This represents the arithmetic average and is a measure of central
tendency commonly used in descriptive statistics.
2. Which of the following is the middle value in an ordered data set?
A. Mean
B. Mode
C. Median
D. Range
E. Standard deviation
Correct answer: C
RATIONALE: The median is the value that divides the data into two
equal halves when arranged in order. It is particularly useful for data
sets with outliers since it is not affected by extreme values, unlike the
mean.
,3. A data set has a mean of 50 and a standard deviation of 10. What
does a standard deviation of 10 indicate?
A. The average value is 50
B. The data varies by an average of 10 units from the mean
C. All values are within 10 units of 50
D. The range of data is 10
E. The median is 40
Correct answer: B
RATIONALE: Standard deviation measures the average distance of
each data point from the mean. A standard deviation of 10 means that, on
average, the data points deviate 10 units from the mean of 50.
4. What is the probability of rolling a fair six-sided die and getting a
4?
A. 1/6
B. 1/4
C. 1/3
D. 1/2
E. 2/3
Correct answer: A
RATIONALE: A fair six-sided die has six equally likely outcomes (1,
2, 3, 4, 5, 6). The probability of any single outcome is 1 divided by the
total number of possible outcomes, which is 1/6.
5. If two fair coins are flipped simultaneously, what is the
probability of getting at least one heads?
A. 1/4
B. 1/3
C. 1/2
D. 3/4
E. 1
, Correct answer: D
RATIONALE: The possible outcomes are HH, HT, TH, TT (4 equally
likely outcomes). Three of these outcomes contain at least one heads:
HH, HT, and TH. Therefore, the probability is 3/4. Alternatively, P(at
least one H) = 1 - P(no H) = 1 - 1/4 = 3/4.
6. What is the mean of 4, 6, 8, 10, 12?
A. 6
B. 8
C. 10
D. 12
Correct answer: B
RATIONALE: The mean is calculated by summing all values and
dividing by the number of observations. (4 + 6 + 8 + 10 + 12) / 5 =
= 8.
7. What is the median of 2, 5, 7, 9, 12?
A. 5
B. 6
C. 7
D. 9
Correct answer: C
RATIONALE: The median is the middle value in an ordered data set.
With five values, the third value (7) is the median.
8. What is the mode of 3, 4, 4, 5, 6?
A. 3
B. 4
C. 5
D. 6
Correct answer: B
OBJECTIVE ASSESSMENT EXAM (2026 /
2027) WITH QUESTIONS AND REVISED
ANSWERS, 100% GUARANTEE PASS
(UPDATED)
Core Domains:
• Descriptive Statistics (Measures of Center, Spread, and Graphical
Displays)
• Probability Rules, Counting Principles, and Distributions
• Inferential Statistics (Hypothesis Testing, Confidence Intervals, and
Sampling)
• Data Types and Study Design (Observational vs. Experimental)
• Correlation, Regression, and Bivariate Data
• Normal and Binomial Distributions
• Basic Numeracy and Algebraic Foundations
• Statistical Decision-Making and Interpretation
Introduction:
This comprehensive objective assessment is designed to evaluate the
student's mastery of applied probability and statistical concepts as outlined
in the WGU C955 curriculum. The examination covers a wide range of
topics including descriptive statistics, probability theory, inferential
statistics, and data interpretation. The format includes multiple-choice
questions that test both foundational knowledge and applied analytical
skills. Each question is accompanied by a verified answer and a detailed
rationale to reinforce understanding and promote conceptual clarity. This
,resource is aligned with the latest 2026/2027 course objectives and is
designed to prepare students for success on the official WGU C955
Objective Assessment exam.
SECTION ONE: QUESTIONS 1-200
1. A data set contains the values: 3, 5, 7, 9, 11. What is the mean of
this data set?
A. 5
B. 7
C. 8
D. 9
E. 10
Correct answer: B
RATIONALE: The mean is calculated by summing all values and
dividing by the number of observations. (3 + 5 + 7 + 9 + 11) / 5 =
= 7. This represents the arithmetic average and is a measure of central
tendency commonly used in descriptive statistics.
2. Which of the following is the middle value in an ordered data set?
A. Mean
B. Mode
C. Median
D. Range
E. Standard deviation
Correct answer: C
RATIONALE: The median is the value that divides the data into two
equal halves when arranged in order. It is particularly useful for data
sets with outliers since it is not affected by extreme values, unlike the
mean.
,3. A data set has a mean of 50 and a standard deviation of 10. What
does a standard deviation of 10 indicate?
A. The average value is 50
B. The data varies by an average of 10 units from the mean
C. All values are within 10 units of 50
D. The range of data is 10
E. The median is 40
Correct answer: B
RATIONALE: Standard deviation measures the average distance of
each data point from the mean. A standard deviation of 10 means that, on
average, the data points deviate 10 units from the mean of 50.
4. What is the probability of rolling a fair six-sided die and getting a
4?
A. 1/6
B. 1/4
C. 1/3
D. 1/2
E. 2/3
Correct answer: A
RATIONALE: A fair six-sided die has six equally likely outcomes (1,
2, 3, 4, 5, 6). The probability of any single outcome is 1 divided by the
total number of possible outcomes, which is 1/6.
5. If two fair coins are flipped simultaneously, what is the
probability of getting at least one heads?
A. 1/4
B. 1/3
C. 1/2
D. 3/4
E. 1
, Correct answer: D
RATIONALE: The possible outcomes are HH, HT, TH, TT (4 equally
likely outcomes). Three of these outcomes contain at least one heads:
HH, HT, and TH. Therefore, the probability is 3/4. Alternatively, P(at
least one H) = 1 - P(no H) = 1 - 1/4 = 3/4.
6. What is the mean of 4, 6, 8, 10, 12?
A. 6
B. 8
C. 10
D. 12
Correct answer: B
RATIONALE: The mean is calculated by summing all values and
dividing by the number of observations. (4 + 6 + 8 + 10 + 12) / 5 =
= 8.
7. What is the median of 2, 5, 7, 9, 12?
A. 5
B. 6
C. 7
D. 9
Correct answer: C
RATIONALE: The median is the middle value in an ordered data set.
With five values, the third value (7) is the median.
8. What is the mode of 3, 4, 4, 5, 6?
A. 3
B. 4
C. 5
D. 6
Correct answer: B
