Probability Question

Question

An unfair coin shows heads with probability p and tails with probability 1 − p. Suppose this coin is flipped n times. Let A be the event that heads comes up exactly h times. Find P(A) .

Answer 1

The answer is: use the binomial distribution

P(x) = C(n,x) p^x(1-p)^n-x

In this case, A is the event that x = h, so P(A) = C(n,h) p^h(1-p)^n-h