SOLUTION: Niall rolls a fair die 50 times. Find: a) the expected number of odd numbers b) the variance of odd numbers c) the standard deviation of odd numbers

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Question 367577: Niall rolls a fair die 50 times. Find:
a) the expected number of odd numbers
b) the variance of odd numbers
c) the standard deviation of odd numbers
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
The exercise becomes a binomial experiment with P(odd)= p = 0.5 and P(even) = q= 0.5.
a)the expectation is mu+=+np+=+50%2A0.5+=+25odd numbers.
b) the variance is sigma%5E2+=+npq+=+50%2A.5%2A.5+=+12.5
c) the SD is just the square root of (b)--around 3.54.