Originally Posted by ophir silverman
sorry for this beginner question but:
I have been trying to find the prob of floping 2 pair or better (2pair -full house) with two unpaired cards and It just doesnt seem right to me.
please if anybody can point out my mistake It would be awsome .
why is this wrong?
6x5x48/3!= 240 240/19600= 0.0122 ansx100 = 1.22%
You have to do the full houses (and quads) separately since multiplying by 48 will count them multiple times. For 2-pair or trips you multiply by 44 unpaired cards instead of 48, and then divide by 2 not 3! since there are 6*5/2 combinations of 2 cards that match your hand, times 44 ways to choose the unpaired card. Assuming you want 2-pair made with both hole cards, trips, full house, or quads, it is
(6*5*44/2 + 6*5*4/3!)/19600
where the 6*5*44/2 is for 2-pair or trips, and the 6*5*4/3! is for a full house or quads. It's not clear whether you wanted to include trips or quads. It looks like you were trying to include trips, but then you say that you are using both hole cards. If you mean that you have to pair both hole cards, then you can't make trips or quads. You can also calculate each hand type separately:
2-pair: 3*3*44/19600 =~ 2.02%
trips: 2*(3*2/2)*44/19600 =~ 1.35%
full house: 2*(3*2/2)*3/19600 =~ 0.0918%
quads: 2/19600 =~ 0.0102%
total =~ 3.47%
as before. Note that the factor of 2 for the trips and full houses is for the 2 ranks that can make the trips.