SOLUTION: A binomial has a mean of 5.2 and a variance equal to 3.12. Find "n" and "p".

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Question 998628: A binomial has a mean of 5.2 and a variance equal to 3.12. Find "n" and "p".
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
mean=np
variance= np(1-p)
5.2=np
3.12=np(1-p)
n=(5.2)/p
3.12=5.2/p * p * (1-p)=5.2(1-p)
3.12=5.2-5.2p
-2.08=-5.2p
p=0.4
n=13
np(1-p)=0.24*13=3.12