SOLUTION: The mean and variance of a Binomial variable X with parameters n and p are 16 and 8. Find P(X1) and P(X>2).

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Question 1176098: The mean and variance of a Binomial variable X with parameters n and p are 16 and 8. Find P(X1) and P(X>2).
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
the mean is np=16
the variance is np (1-p)=8
so 16(1-p)=8
1-p=1/2
p=0.50
n=32
p=0.5
mean 16
variance 8
probability x=1 is 32C)*0.5^1*0.5^31=7 x 10^(-9)
probability x>2 is 1- probability x=2 essentially, which is 1=32C2*0.5^32=1.