What is the conditional probability that exactly four heads appear when a coin is flipped five times.? It is given that the first flip came up heads?
flip. The number of heads in these 4 flips ~B(4,0.5), so is:
p = prob(4 H from 5 flips|first is H) = b(3;4,0.5)
Now look the probability mass function for the binomial distribution up in your
notes and/ot text to evaluate p.