[Cobra]

There is some confusion of what information you are looking for. Lets assume you have aces, the flop comes with two to a suit and you hold one of that suit. The following is the probability that if one of your opponents has two of the suit in question he will hit a flush.

You: [img]/images/graemlins/spade.gif[/img] [img]/images/graemlins/diamond.gif[/img]
Flop: [img]/images/graemlins/spade.gif[/img] [img]/images/graemlins/spade.gif[/img] [img]/images/graemlins/heart.gif[/img]
Opponent: [img]/images/graemlins/spade.gif[/img] [img]/images/graemlins/spade.gif[/img]

In this situation there would be 45 unknown cards eight are spades and 37 are blanks.

Probability of ending up with 3 [img]/images/graemlins/spade.gif[/img]= 8*37/(45c2)=29.9%

Probability of ending up with 4 [img]/images/graemlins/spade.gif[/img]=(8c2)/(45c2)=2.8%

Note that if you end up with four spades your opponent would loose. So the chance of you loosing to a flush draw is 29.9%.

Cobra