SOLUTION: the final exam in a math coures consists of 40 multiple-choise question. each question has 4 possible answers, and only 1 of them is correct. an unprepared student makes random gue

Question 437125: the final exam in a math coures consists of 40 multiple-choise question. each question has 4 possible answers, and only 1 of them is correct. an unprepared student makes random guesses for all of the answers. find the mean and standard deviation for the number of correct anwers for such student.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
the final exam in a math course consists of 40 multiple-choise question. each question has 4 possible answers, and only 1 of them is correct. an unprepared student makes random guesses for all of the answers. find the mean and standard deviation for the number of correct anwers for such student.
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Binomial Problem with n=40 and p = 1/4
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mean = np = (1/4)(40) = 10
std = sqrt[npq] = sqrt[10*(3/4)] = 2.7386
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Cheers,
Stan H.
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