StraighterLine Statistics Final Exam Practice Test
2026: 100 Questions & Answers with Detailed
Rationales | MAT202 Introduction to Statistics Exam
Prep
1. Which statement best describes a population?
A. A subset selected from a larger group
B. The complete group of individuals or observations of interest
C. The numerical summary calculated from a sample
D. A graph representing collected data
Correct Answer: B
Rationale: A population consists of the entire group about which a researcher wants to draw
conclusions. A sample is a subset of that population.
2. A researcher randomly selects 100 students from a university of 5,000
students and records their GPA. The 100 students represent the:
A. Population
B. Parameter
C. Sample
D. Census
Correct Answer: C
Rationale: The 100 selected students are a subset of the 5,000 students, so they constitute the
sample.
,3. Which measure of center is generally most resistant to extreme outliers?
A. Mean
B. Median
C. Variance
D. Standard deviation
Correct Answer: B
Rationale: The median is based on the middle position of ordered observations and is much less
affected by unusually large or small values than the mean.
4. Consider the data set:
4, 6, 8, 10, 12
What is the mean?
A. 6
B. 7
C. 8
D. 10
Correct Answer: C
Rationale:
\[ \bar{x}=\frac{4+6+8+10+12}{5}=\frac{40}{5}=8 \]
5. Which graph is generally most appropriate for displaying the distribution
of a quantitative variable?
A. Histogram
B. Pie chart
C. Bar chart of categories
D. Pareto chart only
Correct Answer: A
Rationale: A histogram displays the distribution of numerical data by grouping observations into
intervals.
,6. A distribution has a long tail extending toward larger values. This
distribution is:
A. Left-skewed
B. Right-skewed
C. Symmetric
D. Uniform
Correct Answer: B
Rationale: A long tail toward higher numerical values indicates positive, or right, skewness.
7. If two events cannot occur at the same time, they are:
A. Independent
B. Conditional
C. Mutually exclusive
D. Complementary
Correct Answer: C
Rationale: Mutually exclusive events have no outcomes in common and therefore cannot occur
simultaneously.
8. A fair six-sided die is rolled once. What is the probability of obtaining a 4?
A. 1/2
B. 1/3
C. 1/6
D. 4/6
Correct Answer: C
Rationale: There is one favorable outcome out of six equally likely outcomes:
\[ P(4)=\frac16 \]
, 9. If \(P(A)=0.40\), what is \(P(A^c)\)?
A. 0.20
B. 0.40
C. 0.60
D. 1.40
Correct Answer: C
Rationale: The complement rule is:
\[ P(A^c)=1-P(A)=1-0.40=0.60 \]
10. If events A and B are independent, which relationship is true?
A. \(P(A\cap B)=0\)
B. \(P(A\cap B)=P(A)P(B)\)
C. \(P(A)=P(B)\)
D. \(P(A\cup B)=0\)
Correct Answer: B
Rationale: For independent events, the probability that both occur equals the product of their
individual probabilities.
11. A random variable that can take only countable values such as 0, 1, 2, 3
is called:
A. Continuous
B. Discrete
C. Nominal
D. Ordinal
Correct Answer: B
Rationale: Discrete random variables take distinct, countable numerical values. The number of
defective products is an example.
2026: 100 Questions & Answers with Detailed
Rationales | MAT202 Introduction to Statistics Exam
Prep
1. Which statement best describes a population?
A. A subset selected from a larger group
B. The complete group of individuals or observations of interest
C. The numerical summary calculated from a sample
D. A graph representing collected data
Correct Answer: B
Rationale: A population consists of the entire group about which a researcher wants to draw
conclusions. A sample is a subset of that population.
2. A researcher randomly selects 100 students from a university of 5,000
students and records their GPA. The 100 students represent the:
A. Population
B. Parameter
C. Sample
D. Census
Correct Answer: C
Rationale: The 100 selected students are a subset of the 5,000 students, so they constitute the
sample.
,3. Which measure of center is generally most resistant to extreme outliers?
A. Mean
B. Median
C. Variance
D. Standard deviation
Correct Answer: B
Rationale: The median is based on the middle position of ordered observations and is much less
affected by unusually large or small values than the mean.
4. Consider the data set:
4, 6, 8, 10, 12
What is the mean?
A. 6
B. 7
C. 8
D. 10
Correct Answer: C
Rationale:
\[ \bar{x}=\frac{4+6+8+10+12}{5}=\frac{40}{5}=8 \]
5. Which graph is generally most appropriate for displaying the distribution
of a quantitative variable?
A. Histogram
B. Pie chart
C. Bar chart of categories
D. Pareto chart only
Correct Answer: A
Rationale: A histogram displays the distribution of numerical data by grouping observations into
intervals.
,6. A distribution has a long tail extending toward larger values. This
distribution is:
A. Left-skewed
B. Right-skewed
C. Symmetric
D. Uniform
Correct Answer: B
Rationale: A long tail toward higher numerical values indicates positive, or right, skewness.
7. If two events cannot occur at the same time, they are:
A. Independent
B. Conditional
C. Mutually exclusive
D. Complementary
Correct Answer: C
Rationale: Mutually exclusive events have no outcomes in common and therefore cannot occur
simultaneously.
8. A fair six-sided die is rolled once. What is the probability of obtaining a 4?
A. 1/2
B. 1/3
C. 1/6
D. 4/6
Correct Answer: C
Rationale: There is one favorable outcome out of six equally likely outcomes:
\[ P(4)=\frac16 \]
, 9. If \(P(A)=0.40\), what is \(P(A^c)\)?
A. 0.20
B. 0.40
C. 0.60
D. 1.40
Correct Answer: C
Rationale: The complement rule is:
\[ P(A^c)=1-P(A)=1-0.40=0.60 \]
10. If events A and B are independent, which relationship is true?
A. \(P(A\cap B)=0\)
B. \(P(A\cap B)=P(A)P(B)\)
C. \(P(A)=P(B)\)
D. \(P(A\cup B)=0\)
Correct Answer: B
Rationale: For independent events, the probability that both occur equals the product of their
individual probabilities.
11. A random variable that can take only countable values such as 0, 1, 2, 3
is called:
A. Continuous
B. Discrete
C. Nominal
D. Ordinal
Correct Answer: B
Rationale: Discrete random variables take distinct, countable numerical values. The number of
defective products is an example.
