SOLUTION: a quiz consists of 90 multiple choice questions each with five possible answers only one of them is correct. Find the mean and standard deviation of the number of correct answers.

Algebra ->  Probability-and-statistics -> SOLUTION: a quiz consists of 90 multiple choice questions each with five possible answers only one of them is correct. Find the mean and standard deviation of the number of correct answers.       Log On


   

Question 750591: a quiz consists of 90 multiple choice questions each with five possible answers only one of them is correct. Find the mean and standard deviation of the number of correct answers.
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
mean, E(X) = np
= 90%281%2F5%29
= highlight%2818%29
standard deviation =sqrt%28npq%29
= sqrt%2890%280.2%29%280.8%29%29
= sqrt%2814.4%29
≈ highlight%283.7947%29