A test has multiple choice questions with 5 choices for each answer; only one answer is correct for each question. Suppose a stu
dent guesses the answer to each question. Assuming the guesses are independent, find the probability that the student will guess correctly when answering two questions.
Each question has 5 choices for each answer, the probability that the student guesses right would be 1/5.
We need to know the probability that the student will guess correctly when answering two questions. To do this, the student would have to guess correctly answer one AND answer two.
Since the student needs to guess both (one AND two) we are going to multiply both probabilities:
P(guess correctly answer 1) x P(guess correctly answer 2)
(1/5) x (1/5) = 1/25
Therefore the probability that the student will guess correctly when answering two questions is 1/25
