Flush draw odds?

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Gen1GT

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If I'm holding two spades, what are the chances of three more coming up in the community?
 
t1riel

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It depends how many players are at your table.
 
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Gen1GT

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9 players, for tournement's sake...
 
t1riel

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So, it's you and nine other players. There are 13 spades in the deck. You have two of them so there are 11 left in the deck. Each player has two cards so there are 42 cards left in the deck. So, the best chance you have of getting three spades on the community is 26%. Chances are it's less than that because you don't know how many spades, if any, were dealt to the other players.
 
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bellhead1970

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I heard once about 6% to hit a flush...That's without starting with two of a kind.
 
ChuckTs

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t1riel said:
So, it's you and nine other players. There are 13 spades in the deck. You have two of them so there are 11 left in the deck. Each player has two cards so there are 42 cards left in the deck. So, the best chance you have of getting three spades on the community is 26%. Chances are it's less than that because you don't know how many spades, if any, were dealt to the other players.
Tim you are calculating the % of spades in the deck - it's completely different from the probability of you flopping a flush.

odds of flopping a flush with 2 suited hole cards are (stolen from KD's post:https://www.cardschat.com/showthread.php?t=69737&highlight=odds) 118:1 or 0.84%.

Odds of hitting a flush with 2 suited hole cards by the river are 15:1 or 6.4%.

To calculate, you have to take P(1st spade)*P(2nd spade)*P(3rd spade) where P(x) is probability of x.

Think about it - with suited cards, do you flop a flush 1 in 4 times (%26)? If you do, then give me some of whatever you're eating for breakfast!
 
ChuckTs

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To calculate yourself:

To calculate the probability of an event happening, you divide (number of times event can occur) by (total possible outcomes). For instance, the probability of rolling a 6 on a 6-sided die: there is 1 six (event), and 6 total sides (total outcomes), so the probability is 1/6.

To calculate the probability of multiple events happening (such as the multiple cards coming up with the same suit), then you take the probability (by method above) of each, and multiply them together. For instance, the probability of getting AA dealt to you:

P(first ace)
= 4(possible aces)/52(possible cards) and

P(second ace)
= 3(possible aces left)/51(possible cards left).

Then multiply them together, so you get:

P(first ace)
= 4/52
= 1/13

P(second ace)
= 3/51
= 1/17

P(getting dealt AA)
= 1/13*1/17
= 1/221 which is also equal to ~%0.5 or 220:1.

Sorry; feel like rambling a bit :D:
so the probability of flopping a flush can be found this way:

P(1st spade)*P(2nd spade)*P(3rd spade)
= (11/50)*(10/49)*(9/48)
= 33/3920 = %0.84
 
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Gen1GT

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Thanks Chuck! You own. So basically, when I've got an A4 suited(or similar hand), my pot odds are 15:1. That's the answer I was looking for.
 
ChuckTs

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Gen1GT said:
Thanks Chuck!
You're very welcome :)

So basically, when I've got an A4 suited(or similar hand), my pot odds are 15:1.
Errrr - not exactly.

First off, 'pot odds' are the ratio between [amount of the pot plus that bet facing you] and [the bet facing you]. For example someone bets 500 into you, and there's another 1000 in the middle, you're getting 1500(1000+500):500 or 3:1.
You're thinking of drawing odds.

In order to get proper odds to call an A4 suited based on the fact that you're chasing only the flush, then you'd need 15:1 pot odds before the flop, and....agh nevermind that example :p

Think of it this way:

Forget about those odds when you're playing something like Ax suited.
Play those types of hands only when you get in from late position, and there have been a few limpers ahead of you to give you good pot odds. Then if you get a flush draw on the flop, consider these drawing odds when faced with a bet:

Flush draw odds:
flop to the turn: 4.22:1
turn to the river: 4.11:1

So in order to chase the draw, you'll need around those odds to call profitably.
 
Ronaldadio

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Without getting too technical...

I was told it was about 17:1 chance of hitting a flush when u start with 2 suited cards in the pocket. That why I get driven mad when someone hits a flush draw with something like Q4 hearts in the pocket and they think because its soooooooooted they have a great chance.

Again, roughly, if u r forced allin at the flop and u r one card short of a flush, u have a 50% chance of hitting.

However, if u r looking at the pot odds as Chuck explained, in the same scenarion, u have a 25% chance of hitting on the turn, then a 25% chance of hitting on the river.

I hope I`m not repeating what has been said, but that is how I work in out.

Ronaldadio
 
Bombjack

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It's 35%, not 50%, to hit a flush by the river, from a draw on the flop. And you're about 20% to hit on each street individually.

The 17:1 stat shows why you need extra value, i.e. high cards, connected cards, to play a suited hand.
 
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