SOLUTION: A multiple choice test consists of 60 questions. Each question has 4 possible answers of which one is correct. If all answers are random guesses, estimate the probability of gettin

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Question 438896: A multiple choice test consists of 60 questions. Each question has 4 possible answers of which one is correct. If all answers are random guesses, estimate the probability of getting at least 20% correct.
a. 0.1492 b. 0.0901 c. 0.8508 d. 0.3508 e. None of the above
Answer by ewatrrr(24785) About Me  (Show Source):
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Hi

A multiple choice test consists of 60 questions. 

Each question has 4 possible answers of which one is correct. 

probability of getting at least 20% correct (min of 12 correct out of 60)

 P(answering question correctly) = .25

 using a bionomial distribution calculator p = .25 , n = 60 and x = 12

 P(X ≥ 12) = .8524