SOLUTION: consider a test with 50 multiple-choice questions, each with 5 options. If students guess radomly on the test, what is the expected mean and standard deviation?
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Question 310174: consider a test with 50 multiple-choice questions, each with 5 options. If students guess radomly on the test, what is the expected mean and standard deviation? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! consider a test with 50 multiple-choice questions, each with 5 options. If students guess radomly on the test, what is the expected mean and standard deviation?
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Binomial problem with n = 50 and p = 1/5
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mean = np = 50*1/5 = 10
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std = sqrt(npq) = sqrt(10(4/5)) = sqrt(8) = 2sqrt(2)
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Cheers,
stan H.
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