Qm
Statistics

Mean and variance of a random-guess quiz score

binomialmoments

A student guesses on all 40 true/false questions of a quiz, getting each one right independently with probability p=0.5p = 0.5. Let CC be the number of correct answers.

What are the mean and variance of CC?

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The Binomial DistributionCumulants and the Cumulant Generating FunctionExpectation, Variance & MomentsMethod of Moments and GMMMoment Generating Functions

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