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dux
06-02-2003, 12:28 AM
If I see the flop in EP at NL with the following hands:

AA KK QQ JJ TT 99
AKs AQs AJs
KQs KJs
QJs
JTs
AKo AQo KQ

How do I work out the correct probability of me seeing the flop? I started writing down some numbers trying to do it systematically like this
Pr(Ace first card) = 1/13 * Pr(Any A, K, Q, Js) = 12/51
Pr(K first card) = 1/13 * Pr(Any Q, Js) = 5/51
etc.

Then I realised that I may be not accounting for an ace on the 2nd card, because AK and KA are different when you are doing probability this way...and is the 1/13 for a K falling wrong because I have already factored in that it isn't an ace...I'm getting way too confused here. Haven't done maths for a year now.

I'm not asking for anybody to work it out for me, I'm just asking what is the correct way to systematically work out the probability of me seeing the flop with a certain group of hands. Is there an easier way using nCr or nPr?

Thanks in advance.

Glenn
06-02-2003, 04:21 AM
You are making it way too complicated.

There are 52 * 51 / 2 = 1326 distinct starting hands.

Each pair can be made 6 ways, each suited hand 4 ways, and each offsuit hand 12 ways.

so your answer would be

Pairs: 6*6 = 36 ways
Suited hands: 7*4 = 28 ways
Offsuit hands: 12*3 = 36 ways

Total = 100 hands out of 1326 total hands = 7.54%

dux
06-02-2003, 09:02 AM
And that's it? Thanks a lot, saved me a lot of time. 7.54%? That's a small number. I'll work the other positions out myself, which shouldn't be too hard. /forums/images/icons/crazy.gif

CreamPuff
06-02-2003, 05:02 PM
Each offsuit hand can be made 16 ways.
So your % is actual higher.

keerok
06-02-2003, 06:24 PM
</font><blockquote><font class="small">In reply to:</font><hr />
Each offsuit hand can be made 16 ways.
So your % is actual higher.

[/ QUOTE ]

Each non-pair hand can be made 16 ways.
12 of these are offsuit, 4 are suited.

dux
06-05-2003, 02:37 AM
I think you are right. So the percentage I worked out is correct?

CreamPuff
06-06-2003, 05:21 AM
He is right.
Anyways, assuming your %'s are right, keep in mind
that you are talking about your hands you play
outside the blinds...
So when you see people say a pro may play between
15-25% (maybe 30 tops) they are including SB
and BB which add significantly to %.

NutJob
06-06-2003, 01:13 PM
The probability of seeing the flop from EP with one of those hands is reduced in direct proportion to the number of players at your table who watched Gus Hansen on WPT, as they take you all in with 32o or AA....your guess is as good as Sextons!