If a student randomly guesses at 20 multiple-choice questions, find the probability that the student gets exactly four correct. Each question has four possible choices.
A) 0.190
B) 0.162
C) 0.085
D) 0.218

Question

Quizplus · Accepted Answer

The probability of getting exactly four correct answers out of 20 multiple-choice questions, each with four possible choices, is 0.190. This can be calculated using the binomial distribution formula:P(X = k) = (n! / (k!(n-k)!)) * p^k * (1-p)^(n-k)where:n is the number of trials (20)k is the number of successes (4)p is the probability of success on each trial (1/4)Plugging these values into the formula, we get:P(X = 4) = (20! / (4!(20-4)!)) * (1/4)^4 * (3/4)^(20-4) = 0.190

If a Student Randomly Guesses at 20 Multiple-Choice Questions, Find