Introduction to Probability: Key Concepts and
Formulas for Students UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
What is the probability of at least one head in two flips of a coin? - CORRECT
ANSWER 0.75
What are revised probabilities of events based on additional information called? - CORRECT
ANSWER Posterior probabilities
How are posterior probabilities computed? - CORRECT ANSWER Using Bayes'
theorem
What is the complement of P(A | B)? - CORRECT ANSWER P(Ac | B)
What is an element of the sample space? - CORRECT ANSWER Sample point
How is the probability of an intersection of two events computed? - CORRECT
ANSWER Using the multiplication law
If A and B are mutually exclusive, what is true? - CORRECT ANSWER P(A ∩ B) = 0
What are posterior probabilities? - CORRECT ANSWER Conditional probabilities
What is the range of probability? - CORRECT ANSWER 0 to 1, inclusive
What is the probability of the sun rising tomorrow? - CORRECT ANSWER 1
What is a process that generates well-defined outcomes? - CORRECT ANSWER An
experiment
, If a fair coin is flipped five times and lands heads each time, what is the probability of heads
on the next flip? - CORRECT ANSWER 0.5
If there is a 60% chance of getting stuck in traffic, what is the probability of getting stuck in
traffic on two separate days? - CORRECT ANSWER 0.36
What does a sample point refer to? - CORRECT ANSWER Individual outcome of an
experiment
What is the collection of all possible sample points in an experiment? - CORRECT
ANSWER The sample space
If 20% of people at a picnic got food poisoning, what percent did NOT get food poisoning? -
CORRECT ANSWER 80%
What does the sample space refer to? - CORRECT ANSWER The set of all possible
experimental outcomes
If an experiment has four possible results on the first step, three on the second, and two on the
third, what is the total number of experimental outcomes? - CORRECT ANSWER 24
How many sample points are there in an experiment of tossing four coins? - CORRECT
ANSWER 16
In a lottery with three urns containing chips numbered 0 to 9, what is the total number of
sample points? - CORRECT ANSWER 1,000
How many sample points are there when checking three applications for admission to a
university? - CORRECT ANSWER 8
Formulas for Students UPDATED ACTUAL
QUESTIONS AND CORRECT ANSWERS
What is the probability of at least one head in two flips of a coin? - CORRECT
ANSWER 0.75
What are revised probabilities of events based on additional information called? - CORRECT
ANSWER Posterior probabilities
How are posterior probabilities computed? - CORRECT ANSWER Using Bayes'
theorem
What is the complement of P(A | B)? - CORRECT ANSWER P(Ac | B)
What is an element of the sample space? - CORRECT ANSWER Sample point
How is the probability of an intersection of two events computed? - CORRECT
ANSWER Using the multiplication law
If A and B are mutually exclusive, what is true? - CORRECT ANSWER P(A ∩ B) = 0
What are posterior probabilities? - CORRECT ANSWER Conditional probabilities
What is the range of probability? - CORRECT ANSWER 0 to 1, inclusive
What is the probability of the sun rising tomorrow? - CORRECT ANSWER 1
What is a process that generates well-defined outcomes? - CORRECT ANSWER An
experiment
, If a fair coin is flipped five times and lands heads each time, what is the probability of heads
on the next flip? - CORRECT ANSWER 0.5
If there is a 60% chance of getting stuck in traffic, what is the probability of getting stuck in
traffic on two separate days? - CORRECT ANSWER 0.36
What does a sample point refer to? - CORRECT ANSWER Individual outcome of an
experiment
What is the collection of all possible sample points in an experiment? - CORRECT
ANSWER The sample space
If 20% of people at a picnic got food poisoning, what percent did NOT get food poisoning? -
CORRECT ANSWER 80%
What does the sample space refer to? - CORRECT ANSWER The set of all possible
experimental outcomes
If an experiment has four possible results on the first step, three on the second, and two on the
third, what is the total number of experimental outcomes? - CORRECT ANSWER 24
How many sample points are there in an experiment of tossing four coins? - CORRECT
ANSWER 16
In a lottery with three urns containing chips numbered 0 to 9, what is the total number of
sample points? - CORRECT ANSWER 1,000
How many sample points are there when checking three applications for admission to a
university? - CORRECT ANSWER 8
