On a very short quiz, there is one multiple choice question with 5 possible choices (a, b, c, d, e) and one true or false question. Assume you are taking the quiz but do not have any idea what the correct answer is to either question. You mark an answer to each question anyway. Assume that the events are independent of each other.

Question

A) What is the probability that you have given the correct answer to both questions?

B) What is the probability that only one of the two answers is correct?

C) What is the probability that neither answer is correct?

D) What is the probability that only your answer to the multiple choice question is correct?

E) What is the probability that you have answered only the true or false question correctly?

Answer 1

Probability of all/both events occurring is found by multiplying the individual probabilities.

A) 1/5 * 1/2 = ?

Probability of either/or events occurring is found by adding the individual probabilities.

B) Follow above instructions.

c) (1-1/5)(1-1/2) = ?

This info should lead you to figuring out D and E.

Answer 2

15