SOLUTION: A quiz consists of 20 true or false questions. If the student guesses on each question, what is the Variance and the standard deviation of the number of correct answers?

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Question 1178702: A quiz consists of 20 true or false questions. If the student guesses on each question, what is the Variance and the standard deviation of the number of
correct answers?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!

Hi
20 t or false questions guessed.  p(correct answer) =  1/2 
mean =  20(1/2) = 10
variance = 10(1-p) = 10(1/2) = 5
sd = √5 =    

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