1. What is the mean of the following data: 5, 8, 12, 15, 18?
A. 12
B. 10.5
C. 13.5
D. 11
Answer: B) 10.5
Rationale: Mean = (5 + 8 + 12 + 15 + 18) / 5 = = 10.5.
2. A die is rolled once. What is the probability of rolling an even
number?
A. 1/6
B. 1/2
C. 2/3
D. 1/3
Answer: B) 1/2
Rationale: The even numbers on a die are 2, 4, and 6, so the probability
is 3/6 = 1/2.
3. Which of the following is the correct notation for a binomial
distribution?
A. Binomial(n, p)
B. N(μ, σ)
C. Poisson(λ)
D. U(a, b)
Answer: A) Binomial(n, p)
Rationale: The binomial distribution is denoted as Binomial(n, p),
where n is the number of trials, and p is the probability of success in
each trial.
,4. The variance of a dataset is 25. What is the standard deviation?
A. 5
B. 25
C. 10
D. 100
Answer: A) 5
Rationale: Standard deviation = √(variance) = √25 = 5.
5. If two events A and B are independent, what is the probability of
both events occurring?
A. P(A) + P(B)
B. P(A) × P(B)
C. P(A | B) × P(B)
D. 1 - P(A ∩ B)
Answer: B) P(A) × P(B)
Rationale: For independent events, the probability of both occurring is
the product of their individual probabilities.
6. Which of the following is NOT a property of the normal
distribution?
A. Symmetrical
B. Mean, median, and mode are equal
C. It has a fixed mean of 1
D. It is bell-shaped
Answer: C) It has a fixed mean of 1
Rationale: The normal distribution has any mean and standard
deviation. It is not fixed at a mean of 1.
7. A random variable follows a normal distribution with a mean of 10
and a standard deviation of 2. What is the probability that the random
variable is between 8 and 12?
, A. 0.6826
B. 0.9545
C. 0.3413
D. 0.9974
Answer: A) 0.6826
Rationale: For a normal distribution, approximately 68% of values lie
within one standard deviation of the mean (between 8 and 12).
8. The probability of an event A occurring is 0.7. What is the
probability that event A does not occur?
A. 0.7
B. 0.3
C. 1.7
D. 0.5
Answer: B) 0.3
Rationale: The probability that event A does not occur is 1 - P(A) = 1 -
0.7 = 0.3.
9. If the correlation coefficient between two variables is 0.8, what does
this indicate?
A. A strong positive linear relationship
B. A strong negative linear relationship
C. No linear relationship
D. A weak negative linear relationship
Answer: A) A strong positive linear relationship
Rationale: A correlation coefficient of 0.8 indicates a strong positive
relationship between the variables.
10. A sample consists of the following values: 4, 7, 10, 13, 16. What is
the median of the sample?
A. 7
A. 12
B. 10.5
C. 13.5
D. 11
Answer: B) 10.5
Rationale: Mean = (5 + 8 + 12 + 15 + 18) / 5 = = 10.5.
2. A die is rolled once. What is the probability of rolling an even
number?
A. 1/6
B. 1/2
C. 2/3
D. 1/3
Answer: B) 1/2
Rationale: The even numbers on a die are 2, 4, and 6, so the probability
is 3/6 = 1/2.
3. Which of the following is the correct notation for a binomial
distribution?
A. Binomial(n, p)
B. N(μ, σ)
C. Poisson(λ)
D. U(a, b)
Answer: A) Binomial(n, p)
Rationale: The binomial distribution is denoted as Binomial(n, p),
where n is the number of trials, and p is the probability of success in
each trial.
,4. The variance of a dataset is 25. What is the standard deviation?
A. 5
B. 25
C. 10
D. 100
Answer: A) 5
Rationale: Standard deviation = √(variance) = √25 = 5.
5. If two events A and B are independent, what is the probability of
both events occurring?
A. P(A) + P(B)
B. P(A) × P(B)
C. P(A | B) × P(B)
D. 1 - P(A ∩ B)
Answer: B) P(A) × P(B)
Rationale: For independent events, the probability of both occurring is
the product of their individual probabilities.
6. Which of the following is NOT a property of the normal
distribution?
A. Symmetrical
B. Mean, median, and mode are equal
C. It has a fixed mean of 1
D. It is bell-shaped
Answer: C) It has a fixed mean of 1
Rationale: The normal distribution has any mean and standard
deviation. It is not fixed at a mean of 1.
7. A random variable follows a normal distribution with a mean of 10
and a standard deviation of 2. What is the probability that the random
variable is between 8 and 12?
, A. 0.6826
B. 0.9545
C. 0.3413
D. 0.9974
Answer: A) 0.6826
Rationale: For a normal distribution, approximately 68% of values lie
within one standard deviation of the mean (between 8 and 12).
8. The probability of an event A occurring is 0.7. What is the
probability that event A does not occur?
A. 0.7
B. 0.3
C. 1.7
D. 0.5
Answer: B) 0.3
Rationale: The probability that event A does not occur is 1 - P(A) = 1 -
0.7 = 0.3.
9. If the correlation coefficient between two variables is 0.8, what does
this indicate?
A. A strong positive linear relationship
B. A strong negative linear relationship
C. No linear relationship
D. A weak negative linear relationship
Answer: A) A strong positive linear relationship
Rationale: A correlation coefficient of 0.8 indicates a strong positive
relationship between the variables.
10. A sample consists of the following values: 4, 7, 10, 13, 16. What is
the median of the sample?
A. 7
