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Pocket10sMedic
02-22-2005, 06:51 PM
*I'm new to the whole idea of probability, so don't crucify me if this question has been asked before*

I'm playing 3/6 at the local B&M yesterday and get KK in EP - I 2 Bet and get 2 callers, includng the BB. Flop comes Q Q Q - My question is, can you show me the equation to calculate the probability of this flop even happening and the probability of the other 2 callers having a Q.

TIA

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AngusThermopyle
02-22-2005, 07:56 PM
[ QUOTE ]
Flop comes Q Q Q -... and the probability of the other 2 callers having a Q.


[/ QUOTE ]

0, in a normal deck /images/graemlins/shocked.gif

Seriously,
Odds of that flop (specifically Q's):
First card a Q:
4/50 -- you remove your K's
Second card a Q:
3/49
Third card a Q:
2/48
All three, multiply
24/117600 or
0.000204081632653061 or
1 in 4900

Probability that the last Q is in one of your 2 opponents hands is really dependent on what range of hands they would play under the circumstances. You know that they are not random cards, and assuming a Q would be more likely in a hand they played, the odds are higher than mere probablitly would predict.

Cobra
02-22-2005, 08:15 PM
The probability that the flop comes three Q's is
(4 choose 3)/(50 choose 3)=.024% or 1 in 4900 hands.

The probability that the flop comes any of the other twelve ranks that you don't hold is 12* above=.24% or 1 in 408 hands.

If you put the two players against you on random hands the probability that one of them has a Q is
=number of opponents * 46/(47 choose 2)=2*4.3%=8.6%

Lets asume that they wouldn't play any Q, assume they would only play a Q paired with a 9 or above that would be
2*1*18/(47 choose 2)=2*1.7%=3.4%

Cobra

bobbyi
02-22-2005, 08:37 PM
There are five cards that we know--two in your hand three on the board. So there 47 cards we don't know. Out of these, 4 are in your opponents hands. There is one queen left so it will be in one of their hands 4/47 times, which is pretty close to 1/12. However, that assumes they are equally likely to play any cards, but in practice people call more with high cards than with low cards, so the real chance of running into a queen is higher than that. We can't calculate it exactly because we don't know exactly what hands your opponents play and how often they will play them in this situation.

housenuts
02-23-2005, 06:13 AM
[ QUOTE ]
There are five cards that we know--two in your hand three on the board. So there 47 cards we don't know. Out of these, 4 are in your opponents hands. There is one queen left so it will be in one of their hands 4/47 times, which is pretty close to 1/12. However, that assumes they are equally likely to play any cards, but in practice people call more with high cards than with low cards, so the real chance of running into a queen is higher than that. We can't calculate it exactly because we don't know exactly what hands your opponents play and how often they will play them in this situation.

[/ QUOTE ]

i would say the chance of running into a queen is actually alot lower than that. out of all the possible hands that have a queen i wouldn't suspect they'd be playing even half of them. there's 4 ways they could have AQ, 2 ways they could have KQ (assuming you have the other 2 k's), 0 QQ, 4 QJ, 4 QT. depending on the opponents you can add a few possibilities, but really that's not many hands compared to the realm of possible hands.

MickeyHoldem
02-23-2005, 12:46 PM
The flop question has been answered by others.

For the other Q... I think the odds are considerably higher than some of the answers that have been given.

The odds you are going to see someone show you that other Q is dependant on your opponents play. You need to figure out the range of hands that are going to be calling your raise from these positions and figure out the ratio: hands with Q/total hands

Example:
Range1: calling 2 bets cold
AA-88: 36
AK: 8
AQ: 4
KQ: 2
AJs: 4
ATs: 4
KJs: 4
QJs: 1
QTs: 1
JTs: 4

# with Q : 8
Total : 68

Range2: calling one bet
all above: 68
77-22: 36
KTs: 4
QTs: 1
Q9s: 1
J9s: 4
T9s: 4
98s: 4
AJ: 16
KQ: 1
ATs: 4
QJ: 3
QT: 3

# with Q: 17
Total: 141

Up against Q = 1 - prob. no Q = 1 - (60/68 * 124/141) = ~.224 or 1 in 4.5

Pocket10sMedic
02-23-2005, 05:29 PM
Thanks again for the help...

Had no read on the person but it was a very loose game.. actually only my second hand played.

Luckily enough for me, she cold-called a 2 bet in MP with Q4o... BLAH

TA

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