SOLUTION: If X is B ~ (n, p) with mean 5 and standard deviation 2. Find the value of n and p.

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Question 1120949: If X is B ~ (n, p) with mean 5 and standard deviation 2. Find the value of n and p.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
the mean of a binomial distribution is np, so np=5
sd is sqrt (var)=sqrt(np(1-p))=2
square the second, and np(1-p)=4
But np=5
so 5(1-p)=4
5-5p=4
-5p=-1
p=0.2
0.2n=5
n=25