SOLUTION: A test consists of 90 multiple choice questions, each with five possible answers, only one of which is correct. Find the mean and the standard deviation of the number of correct a
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Question 490487: A test consists of 90 multiple choice questions, each with five possible answers, only one of which is correct. Find the mean and the standard deviation of the number of correct answers. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A test consists of 90 multiple choice questions, each with five possible answers, only one of which is correct. Find the mean and the standard deviation of the number of correct answers.
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Binomial Problem with n = 90 and p(correct) = 1/5
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mean = np = 90(1/5) = 18
Std = sqrt(npq) = sqrt(18*(4/5)) = 3.7947
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Cheers,
Stan H.
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