SOLUTION: Please help me solve this: Let x be a binomial random variable with n=12 and p=0.3 find p(2<x<9)

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Question 415806: Please help me solve this:
Let x be a binomial random variable with n=12 and p=0.3 find p(2
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi

Note: The probability of x successes in n trials is: 

P = nCx* p%5Ex%2Aq%5E%28n-x%29 where p and q are the probabilities of success and failure respectively. 

In this case p = .3  and  q = .7  and n = 12

nCx = n%21%2F%28x%21%28n-x%29%21%29

P(2< x <9) = P(x > 2)- P(x ≥ 9) = .7455 - .0017 = .7438