[WGU C955 APPLIED PROBABILITY AND STATISTICS
FINAL EXAM] – QUESTIONS AND ANSWERS |
VERIFIED AND WELL DETAILED ANSWERS | PLUS
RATIONALES | GUARANTEED PASS | LATEST EXAM
UPDATE | STUVIA VERIFIED | EXAM PREP | STUDY
GUIDE | PRACTICE TEST
1. Which measure of center is most affected by extreme values?
A. Median
B. Mode
C. Mean
D. Quartile
Correct Answer: C. Mean
Rationale:
The mean uses every value in the data set, making it highly sensitive to unusually large or small
observations.
2. A fair coin is flipped once. What is the probability of getting heads?
A. 1/4
B. 1/2
C. 3/4
D. 1
Correct Answer: B. 1/2
Rationale:
There are two equally likely outcomes when flipping a fair coin, and one outcome is heads.
3. Which graph is best for showing parts of a whole?
A. Histogram
B. Scatterplot
C. Pie chart
D. Boxplot
Correct Answer: C. Pie chart
,Rationale:
A pie chart visually represents categories as proportions of an entire data set.
4. What does a standard deviation measure?
A. Data accuracy
B. Central tendency
C. Probability of success
D. Spread of data values
Correct Answer: D. Spread of data values
Rationale:
Standard deviation describes how far data values typically vary from the mean.
5. Which sampling method gives every member of a population an equal chance of
selection?
A. Convenience sampling
B. Simple random sampling
C. Cluster sampling
D. Judgment sampling
Correct Answer: B. Simple random sampling
Rationale:
Simple random sampling reduces selection bias because each member has an equal probability
of inclusion.
6. A data distribution that is perfectly symmetrical has which relationship?
A. Mean = Median
B. Mean > Median
C. Mean < Mode
D. Median > Mean
Correct Answer: A. Mean = Median
Rationale:
In a perfectly symmetrical distribution, the center values align at the same point.
7. What is the probability of rolling a 3 on a fair six-sided die?
A. 1/2
B. 1/3
C. 1/6
D. 5/6
,Correct Answer: C. 1/6
Rationale:
A fair die has six equally likely outcomes, and only one outcome is a 3.
8. Which term describes the number of times a value occurs in a data set?
A. Variance
B. Frequency
C. Probability
D. Deviation
Correct Answer: B. Frequency
Rationale:
Frequency indicates how often a particular value appears within the data.
9. Which measure is the middle value of an ordered data set?
A. Median
B. Mean
C. Range
D. Variance
Correct Answer: A. Median
Rationale:
The median divides ordered data into two equal halves.
10. A researcher wants to determine whether study time affects test scores. Which variable
is dependent?
A. Study hours
B. Test score
C. Sample size
D. Survey method
Correct Answer: B. Test score
Rationale:
The dependent variable is the outcome being measured and affected by another variable.
11. What is the range of the numbers 4, 8, 10, and 15?
A. 19
B. 10
C. 11
D. 15
, Correct Answer: C. 11
Rationale:
Range equals the maximum value minus the minimum value: 15 − 4 = 11.
12. Which type of correlation exists when two variables move in opposite directions?
A. Positive correlation
B. No correlation
C. Linear correlation
D. Negative correlation
Correct Answer: D. Negative correlation
Rationale:
Negative correlation means one variable increases while the other decreases.
13. What is the primary purpose of inferential statistics?
A. Organize data
B. Describe a sample only
C. Create graphs
D. Draw conclusions about populations
Correct Answer: D. Draw conclusions about populations
Rationale:
Inferential statistics uses sample data to make predictions or conclusions about a larger
population.
14. Which probability value is impossible?
A. 0
B. 0.5
C. 1
D. 1.2
Correct Answer: D. 1.2
Rationale:
Probabilities must fall between 0 and 1 inclusive.
15. What does a histogram display?
A. Relationship between variables
B. Frequency distribution of quantitative data
C. Exact percentages only
D. Categorical comparisons only
FINAL EXAM] – QUESTIONS AND ANSWERS |
VERIFIED AND WELL DETAILED ANSWERS | PLUS
RATIONALES | GUARANTEED PASS | LATEST EXAM
UPDATE | STUVIA VERIFIED | EXAM PREP | STUDY
GUIDE | PRACTICE TEST
1. Which measure of center is most affected by extreme values?
A. Median
B. Mode
C. Mean
D. Quartile
Correct Answer: C. Mean
Rationale:
The mean uses every value in the data set, making it highly sensitive to unusually large or small
observations.
2. A fair coin is flipped once. What is the probability of getting heads?
A. 1/4
B. 1/2
C. 3/4
D. 1
Correct Answer: B. 1/2
Rationale:
There are two equally likely outcomes when flipping a fair coin, and one outcome is heads.
3. Which graph is best for showing parts of a whole?
A. Histogram
B. Scatterplot
C. Pie chart
D. Boxplot
Correct Answer: C. Pie chart
,Rationale:
A pie chart visually represents categories as proportions of an entire data set.
4. What does a standard deviation measure?
A. Data accuracy
B. Central tendency
C. Probability of success
D. Spread of data values
Correct Answer: D. Spread of data values
Rationale:
Standard deviation describes how far data values typically vary from the mean.
5. Which sampling method gives every member of a population an equal chance of
selection?
A. Convenience sampling
B. Simple random sampling
C. Cluster sampling
D. Judgment sampling
Correct Answer: B. Simple random sampling
Rationale:
Simple random sampling reduces selection bias because each member has an equal probability
of inclusion.
6. A data distribution that is perfectly symmetrical has which relationship?
A. Mean = Median
B. Mean > Median
C. Mean < Mode
D. Median > Mean
Correct Answer: A. Mean = Median
Rationale:
In a perfectly symmetrical distribution, the center values align at the same point.
7. What is the probability of rolling a 3 on a fair six-sided die?
A. 1/2
B. 1/3
C. 1/6
D. 5/6
,Correct Answer: C. 1/6
Rationale:
A fair die has six equally likely outcomes, and only one outcome is a 3.
8. Which term describes the number of times a value occurs in a data set?
A. Variance
B. Frequency
C. Probability
D. Deviation
Correct Answer: B. Frequency
Rationale:
Frequency indicates how often a particular value appears within the data.
9. Which measure is the middle value of an ordered data set?
A. Median
B. Mean
C. Range
D. Variance
Correct Answer: A. Median
Rationale:
The median divides ordered data into two equal halves.
10. A researcher wants to determine whether study time affects test scores. Which variable
is dependent?
A. Study hours
B. Test score
C. Sample size
D. Survey method
Correct Answer: B. Test score
Rationale:
The dependent variable is the outcome being measured and affected by another variable.
11. What is the range of the numbers 4, 8, 10, and 15?
A. 19
B. 10
C. 11
D. 15
, Correct Answer: C. 11
Rationale:
Range equals the maximum value minus the minimum value: 15 − 4 = 11.
12. Which type of correlation exists when two variables move in opposite directions?
A. Positive correlation
B. No correlation
C. Linear correlation
D. Negative correlation
Correct Answer: D. Negative correlation
Rationale:
Negative correlation means one variable increases while the other decreases.
13. What is the primary purpose of inferential statistics?
A. Organize data
B. Describe a sample only
C. Create graphs
D. Draw conclusions about populations
Correct Answer: D. Draw conclusions about populations
Rationale:
Inferential statistics uses sample data to make predictions or conclusions about a larger
population.
14. Which probability value is impossible?
A. 0
B. 0.5
C. 1
D. 1.2
Correct Answer: D. 1.2
Rationale:
Probabilities must fall between 0 and 1 inclusive.
15. What does a histogram display?
A. Relationship between variables
B. Frequency distribution of quantitative data
C. Exact percentages only
D. Categorical comparisons only
