Probability Problem- Please Help!!

[SeanM]

If your hand contains two suited cards there is a 11% chance of flopping a four flush.
If your hand contains two maximum connected cards(two connected cards that can make a straight with 3 cards on either side, 45-TJ) you have a 9.8% chance of a straight draw.

Therefore if you play 45-TJ suited you would have a 20.8% cahnce of a flush or straight draw, correct?

[doormat]

Sean,
Out of 50*49*48 combinations, you have 11*10*39*3 that give you a four flush, and 8*4*40*9 that give you an open ended straight draw. However, you cannot add the two together because you are then counting some things twice - remember that some of your flush draws also contain a straight draw and vice-versa. So the probability of either a flush or a straight draw is lower than the 20.8% you calculate, but of course sometimes you will flop a flush or straight outright, which might be meaningful to include in your calculations.

doormat

[BruceZ]

I computed this recently in this post:

flush draw or straight draw (http://www.twoplustwo.com/forums/showthreaded.php?Cat=&Board=probability&Number=278 662&page=&view=&sb=&o=&vc=1)