A quiz consists of 10 true or false questions. To pass the quiz a student must answer at least eight questionscorrectly. If the student guesses on each question, what is the probability that the student will pass the quiz?
A) 0.055
B) 0.8
C) 0.20
D) 0.08

Question

Quizplus · Accepted Answer

The probability of guessing each question correctly is 0.5. To find the probability of passing (getting at least 8 out of 10 questions right), we calculate the probabilities of getting exactly 8, 9, and 10 questions right and sum them up. Using the binomial probability formula, P(X=k) = C(n, k) * p^k * (1-p)^(n-k), where n=10, p=0.5, k=8, 9, 10, and C(n, k) is the combination of n items taken k at a time, we get the sum of these probabilities as approximately 0.055.

A Quiz Consists of 10 True or False Questions