On a multiple choice test with 18 questions, each question has four possible answers, one of...

On a multiple choice test with 18 questions, each question has four possible answers, one of which is correct. For students who guess at all answers, find the variance for the number of correct answers.

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Expert Solution

n = 18

p = 0.25

Variance = np(1 - p)

= 18 * 0.25 * 0.75

= 3.375

orchestra answered 1 year ago

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