A psychology quiz consists of 20 multiple chice questions with five possible answers for each question. A student, say John, is totally unprepared so randomly guesses the answer to each question. This means that John has a probability of 1/5 - .20 of getting any particular problem correct.Let X equal the number of questions out of the 20 questions that John gets correct. Do the calculations below using R. g. What is the variance of X? h. What is the standard deviation of X? i. What is the variance of the random variable Y = 2X?

MATLAB: An Introduction with Applications
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Author:Amos Gilat
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A psychology quiz consists of 20 multiple chice questions with five possible answers for each question. A student, say John, is totally unprepared so randomly guesses the answer to each question. This means that John has a probability of
1/5 = .20 of getting any particular problem correct. Let X equal the number of questions out of the 20 questions that John gets correct. Do the calculations below using R.
g. What is the variance of X?
h. What is the standard deviation of X?
i. What is the variance of the random variable Y = 2X?
Transcribed Image Text:A psychology quiz consists of 20 multiple chice questions with five possible answers for each question. A student, say John, is totally unprepared so randomly guesses the answer to each question. This means that John has a probability of 1/5 = .20 of getting any particular problem correct. Let X equal the number of questions out of the 20 questions that John gets correct. Do the calculations below using R. g. What is the variance of X? h. What is the standard deviation of X? i. What is the variance of the random variable Y = 2X?
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