INTRODUCTION TO PROBABILITY (ANDERSON,
SEPPÄLÄINEN, VALKÓ EXAM Q&AS
This comprehensive, master test bank provides complete,
copy-pasteable multiple-choice questions directly mapped to
the core concepts of Introduction to Probability (2017) by
Anderson, Seppäläinen, and Valkó. Each question features
professional, exam-ready styling with italicized answers and
detailed, bold-italic rationales designed to maximize student
comprehension. It serves as an essential, high-converting
study resource covering everything from fundamental
combinatorics and conditional probability to continuous joint
distributions and limit theorems.
1. What is the sum of the probabilities of all individual
outcomes in a discrete sample space S?
A) 0
B) 0.5
C) 1
D) Undefined
Answer: C
Rationale: A core axiom of probability states that
the sum of the probabilities of all disjoint
outcomes comprising the entire sample space
must equal 1.
2. If events A and B are mutually exclusive, what is the
value of P(A intersect B)?
A) P(A) * P(B)
B) P(A) + P(B)
, C) 0
D) 1
Answer: C
Rationale: Mutually exclusive events cannot occur
at the same time, meaning their intersection
contains no elements and has a probability of
zero.
3. What is the formula for conditional probability P(A | B)
when P(B) > 0?
A) P(A intersect B) / P(B)
B) P(A) / P(B)
C) P(A union B) / P(B)
D) P(A intersect B) * P(B)
Answer: A
Rationale: Conditional probability scales the
probability of the intersection of A and B by the
probability of the conditioning event B.
4. If events A and B are independent, which of the
following statements is always true?
A) P(A | B) = P(A)
B) P(A intersect B) = 0
C) P(A union B) = P(A) + P(B)
D) P(A | B) = P(B)
Answer: A
Rationale: Independence means that the
occurrence of B provides no information about
the probability of A, so P(A | B) equals P(A).
,5. How many ways can k objects be chosen from a set
of n objects if order does not matter and repetition is
not allowed?
A) n! / (n-k)!
B) n! / (k! (n-k)!)
C) n^k
D) k! / n!
Answer: B
Rationale: This describes combinations,
calculated using the binomial coefficient n choose
k.
6. What is the value of P(A complement), the probability
of the complement of event A?
A) 1 - P(A)
B) P(A) - 1
C) 1 / P(A)
D) -P(A)
Answer: A
Rationale: Since an event and its complement
partition the sample space into a total probability
of 1, the complement is 1 minus P(A).
7. What does a probability mass function (PMF)
describe for a discrete random variable?
A) The cumulative probability up to a value
B) The probability that the random variable takes an
exact specific value
C) The density of probability over an interval
D) The variance of the distribution
, Answer: B
Rationale: A PMF assigns probabilities to each
individual discrete outcome or value that the
random variable can assume.
8. For any random variable X, what is the expected
value of a constant c, E(c)?
A) 0
B) c
C) 1
D) c squared
Answer: B
Rationale: The expected value of a deterministic
constant is simply the constant itself.
9. What is the relationship between variance Var(X) and
expectation E(X)?
A) Var(X) = E(X^2) - (E(X))^2
B) Var(X) = (E(X))^2 - E(X^2)
C) Var(X) = E(X^2) + (E(X))^2
D) Var(X) = E(X) - Var(X)
Answer: A
Rationale: Variance is defined as the mean of the
squares minus the square of the mean.
10. If X and Y are independent random variables,
what is E(X * Y)?
A) E(X) + E(Y)
B) E(X) * E(Y)
C) E(X) / E(Y)
D) 0