PSTAT 10 Final Exam Test Bank Questions
and Answers Updated 2026 | Verified
Statistics Exam Solutions and Complete
Study Guide for A+ Results
• This 200-question PSTAT 10 practice exam covers the full range of introductory
statistics topics tested on the final — from descriptive statistics and probability to
inference and regression — with bolded correct answers and EXPERT RATIONALE
for active recall.
• Study by attempting each question independently first, then check the bolded
correct answer and read the EXPERT RATIONALE to reinforce understanding
before moving on.
1. What is the primary purpose of descriptive statistics?
A) To make inferences about a population based on a sample
B) To test hypotheses about population parameters
C) To calculate probabilities of future events
D) To collect data from a population
E) To summarize and describe the main features of a dataset
Correct Answer: E) To summarize and describe the main features of a dataset
EXPERT RATIONALE: Descriptive statistics organize, summarize, and present data
in a meaningful way using measures like mean, median, and standard deviation,
without drawing conclusions beyond the data itself.
2. Which of the following is an example of a categorical variable?
A) Height in centimeters
B) Number of siblings
C) Temperature in Fahrenheit
D) Eye color
,E) Weight in kilograms
Correct Answer: D) Eye color
EXPERT RATIONALE: Categorical variables represent groups or categories with no
inherent numerical value. Eye color (blue, brown, green) is a classic example, unlike
height or weight which are numerical.
3. The mean of the data set {4, 8, 6, 5, 3, 7} is:
A) 5.0
B) 5.5
C) 5.5
D) 6.0
E) 7.0
Correct Answer: C) 5.5
EXPERT RATIONALE: Add all values: 4+8+6+5+3+7 = 33. Divide by 6 values: 33/6 =
5.5.
4. Which measure of central tendency is most resistant to outliers?
A) Mean
B) Mode
C) Range
D) Median
E) Variance
Correct Answer: D) Median
EXPERT RATIONALE: The median is the middle value and is not influenced by
extreme values. The mean, by contrast, is pulled in the direction of outliers.
,5. A dataset has values {2, 2, 3, 5, 9}. What is the mode?
A) 3
B) 5
C) 9
D) 4.2
E) 2
Correct Answer: E) 2
EXPERT RATIONALE: The mode is the value that appears most frequently. The
value 2 appears twice, more than any other value in the dataset.
6. What does the standard deviation measure?
A) The most frequent value in a dataset
B) The middle value of a dataset
C) The difference between the highest and lowest values
D) The average of all values
E) The average spread of data points around the mean
Correct Answer: E) The average spread of data points around the mean
EXPERT RATIONALE: Standard deviation quantifies how much individual data
points deviate from the mean on average. A larger standard deviation indicates
more variability.
7. If a distribution is right-skewed, which of the following is typically true?
A) Mean < Median < Mode
B) Mean = Median = Mode
, C) Mode > Median > Mean
D) Mean > Median > Mode
E) Median > Mean > Mode
Correct Answer: D) Mean > Median > Mode
EXPERT RATIONALE: In a right-skewed distribution, the tail extends to the right,
pulling the mean upward. The mean is greater than the median, which is greater
than the mode.
8. The interquartile range (IQR) is defined as:
A) Q3 minus the mean
B) Q1 minus Q3
C) The range divided by 2
D) The median of the upper half only
E) Q3 minus Q1
Correct Answer: E) Q3 minus Q1
EXPERT RATIONALE: The IQR measures the spread of the middle 50% of data. It is
calculated as the third quartile (Q3) minus the first quartile (Q1), making it resistant
to outliers.
9. Which of the following best describes a population parameter?
A) A value calculated from sample data
B) A graphical representation of data
C) A probability assigned to an event
D) A numerical characteristic that describes an entire population
E) A statistic used to test a hypothesis
and Answers Updated 2026 | Verified
Statistics Exam Solutions and Complete
Study Guide for A+ Results
• This 200-question PSTAT 10 practice exam covers the full range of introductory
statistics topics tested on the final — from descriptive statistics and probability to
inference and regression — with bolded correct answers and EXPERT RATIONALE
for active recall.
• Study by attempting each question independently first, then check the bolded
correct answer and read the EXPERT RATIONALE to reinforce understanding
before moving on.
1. What is the primary purpose of descriptive statistics?
A) To make inferences about a population based on a sample
B) To test hypotheses about population parameters
C) To calculate probabilities of future events
D) To collect data from a population
E) To summarize and describe the main features of a dataset
Correct Answer: E) To summarize and describe the main features of a dataset
EXPERT RATIONALE: Descriptive statistics organize, summarize, and present data
in a meaningful way using measures like mean, median, and standard deviation,
without drawing conclusions beyond the data itself.
2. Which of the following is an example of a categorical variable?
A) Height in centimeters
B) Number of siblings
C) Temperature in Fahrenheit
D) Eye color
,E) Weight in kilograms
Correct Answer: D) Eye color
EXPERT RATIONALE: Categorical variables represent groups or categories with no
inherent numerical value. Eye color (blue, brown, green) is a classic example, unlike
height or weight which are numerical.
3. The mean of the data set {4, 8, 6, 5, 3, 7} is:
A) 5.0
B) 5.5
C) 5.5
D) 6.0
E) 7.0
Correct Answer: C) 5.5
EXPERT RATIONALE: Add all values: 4+8+6+5+3+7 = 33. Divide by 6 values: 33/6 =
5.5.
4. Which measure of central tendency is most resistant to outliers?
A) Mean
B) Mode
C) Range
D) Median
E) Variance
Correct Answer: D) Median
EXPERT RATIONALE: The median is the middle value and is not influenced by
extreme values. The mean, by contrast, is pulled in the direction of outliers.
,5. A dataset has values {2, 2, 3, 5, 9}. What is the mode?
A) 3
B) 5
C) 9
D) 4.2
E) 2
Correct Answer: E) 2
EXPERT RATIONALE: The mode is the value that appears most frequently. The
value 2 appears twice, more than any other value in the dataset.
6. What does the standard deviation measure?
A) The most frequent value in a dataset
B) The middle value of a dataset
C) The difference between the highest and lowest values
D) The average of all values
E) The average spread of data points around the mean
Correct Answer: E) The average spread of data points around the mean
EXPERT RATIONALE: Standard deviation quantifies how much individual data
points deviate from the mean on average. A larger standard deviation indicates
more variability.
7. If a distribution is right-skewed, which of the following is typically true?
A) Mean < Median < Mode
B) Mean = Median = Mode
, C) Mode > Median > Mean
D) Mean > Median > Mode
E) Median > Mean > Mode
Correct Answer: D) Mean > Median > Mode
EXPERT RATIONALE: In a right-skewed distribution, the tail extends to the right,
pulling the mean upward. The mean is greater than the median, which is greater
than the mode.
8. The interquartile range (IQR) is defined as:
A) Q3 minus the mean
B) Q1 minus Q3
C) The range divided by 2
D) The median of the upper half only
E) Q3 minus Q1
Correct Answer: E) Q3 minus Q1
EXPERT RATIONALE: The IQR measures the spread of the middle 50% of data. It is
calculated as the third quartile (Q3) minus the first quartile (Q1), making it resistant
to outliers.
9. Which of the following best describes a population parameter?
A) A value calculated from sample data
B) A graphical representation of data
C) A probability assigned to an event
D) A numerical characteristic that describes an entire population
E) A statistic used to test a hypothesis
