Question

Find the mean and standard deviation for each binomial random variable: a. n = 52, π = .80 (Round your mean value to 2 decimal places and standard deviation to 4 decimal places.) Mean 41.6

Standard deviation b. n = 90, π = .60 (Round your mean value to 2 decimal places and standard deviation to 4 decimal places.) Mean 54 Standard deviation

c. n = 42, π = .75 (Round your mean value to 2 decimal places and standard deviation to 4 decimal places.) Mean 31.5 Standard deviation

I was able to find the mean but not the standard deviation. For example: np(1-p) For example a. 52(0.80) (1-.80)=41.6 (.2)=8.32

My homework checker is stating that is incorrect and I'm going insane as that is how I thought you figure out the standard deviation. I tried to figure out how to submit it in Excel to figure out the problem to but I need 4 numbers to answer and not sure what to use so that didn't work out for me either. This is a last ditch effort to figure what am I doing wrong.

Answer 1