[jay_shark]

Brizza , these odds change when there are more players seeing the flop .

Also , when a player sees the flop , he does not have a random hand so there is a higher chance that one may flop a set and another may flop two pair . The more players at your table , the more likely this is to be the case .

2)Player 1 has AB and player 2 has CD and assume there are only two players for now and that A,B,C,D are different :

If this were to be the case then the probability is 0 since there are only 3 cards to a flop .

This means there must be one card in common or possibly both ;ie , AB,AC or AB,BC or AB,AB .

P(AB,AC or AB,BC) =[1248/1326*(3*44/1225)*2]*3*2*3/48c3 =0.000211

P(AB,AB)= [1248/1326*9/1225]*2*2*44/48c3 = 0.0000703

Add those two results and you should get 0.000281...

3)[78/1326*72/1225]*2*2*44/48c3 = 0.0000351...