Probability of AT LEAST a four flush

[Dave H.]

Question 1: Are my first 2 assumptions correct given a suited pocket?

Assumption 1: Probability of EXACTLY a four flush on the flop = (C(11,2) * 39) / C(50,3) = .1094

Assumption 2: Probability of EXACTLY a five flush on the flop = C(11,3)/C(50,3) = .0028

Question 2: Do I just sum the above (.1094 + .0028) to arrive at the probability of AT LEAST a four flush on the flop? If not, how would that be computed please?