Can you solve this degeso?

P(B|A)= P(BnA)/P(A)

P(HH|at least 1 head) = P(HHnat least 1 head)/P(at least 1 head)

p(HH n at least 1 head ) = P(HH) (since {HH} is contained in {at least 1 head})
P(HH) = 1/4
P(at least 1 head) = 3/4

P(HH)/P(at least 1 head) = (1/4) / (3/4) = 1/3.