SOLUTION: stephen is taking a twenty question multiple choice test. each question has 5 choices, A B C D or E. only one of the five is correct. If Stephen guesses on every problem, what i

Question 322074: stephen is taking a twenty question multiple choice test. each question has 5 choices, A B C D or E. only one of the five is correct. If Stephen guesses on every problem, what is the probability that he will get exactly 8 correct?
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
stephen is taking a twenty question multiple choice test. each question has 5 choices, A B C D or E. only one of the five is correct. If Stephen guesses on every problem, what is the probability that he will get exactly 8 correct?
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Binomial Problem with n = 20 and p = 1/5
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P(x=8) = 20C8(1/5)^8*(4/5)^12 = 0.0222
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Cheers,
Stan H.
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