SOLUTION: A multiple choice test has 100 questions. For subjects making random guesses for each answer, the mean number of correct answers is 20.0 and the standard deviation of the numbers

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Question 419299: A multiple choice test has 100 questions. For subjects making random guesses for each answer, the mean number of correct answers is 20.0 and the standard deviation of the numbers of correct answers is 4.0. For someone making random guesses for all answers, is it unusual to get 35 correct answers?
Answer by ewatrrr(24785) About Me  (Show Source):
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Hi

 A multiple choice test has 100 questions.

For subjects making random guesses for each answer, the mean number of correct

 answers is 20.0 and the standard deviation of the numbers of correct answers is 4.0.

that is: those having guessed 28 right answers are 2 SD from the mean.. (see graph)

For someone making random guesses for all answers, 

is it unusual to get 35 correct answers? Yes, very elite...group 

97.7% GUESS LESS THAN 28 CORRECT.