Question 1010686



p(x) = c(n,x) * p^x * q^(n-x)


p(x) is the probability of getting exactly x h9its.


c(n,x) is the combination formula of n! / (x! * (n-x)!).


it tells you how many ways you can get x things out of n where order doesn't matter.


p is the probability of success, in this case the probability of getting a hit.


q is the probability of failure, in this case the probability of not getting a hit.


in this formula, q is always equal to 1-p.


x is the number of things you want to choose out of n things.


n is the total number of things you are choosing from.


in your problem, the formula of p(x) = c(n,x) * p^x * q^(n-x) becomes:


p(4) = c(8,4) * .45^4 * .55^4 = .2627 = 26.27%


the total probability is 1 , as it should be.