Odds, NLHE, 4th street FD

[x vikram]

NLHE cash game. 10 handed.

Assuming the you arrive against one player with a flush draw on 4th street, the flop was checked etc.

I have a flush draw and am facing a bet of 2:1 however my chance to hit is 4.5:1.

I was doing some simple maths, assuming the pot is 300$ and the bet on 4th street is 300$ you are getting 2:1 and therefore 3 times you will miss costing you 900$ and 1 time you will hit winning you 600$, does this mean for this move to be +ev you must win more than 300$, possibly gained by betting once hitting and being called?

Just wondering how to make FDs profitable from 4th street.

[WordWhiz]

If it's 300 to call in a 600 pot, you're not getting proper pot odds and should probably fold, unless you think your implied odds are excellent. However, your math is a little funky. A call can only lose $300--the 600 is already in the pot and is not yours.

[Pauwl]

In your description of the times you miss and hit you are assuming that the flush draw is 3:1."3 times you will miss costing you 900$ and 1 time you will hit winning you 600$,". This is incorrect, it should be 4:1. Assuming 4:1 for the draw, you will miss 4 times costing you $1200 and win once earning $600. In order for the play to be +EV you need to get your 4:1 implied odds paid off on the river. This means that you will have to extract an additional $600 from your opponent on the river when you do hit.

[Fishy McDonk]

4th street? You must be a stud player.

[trentk268]

Don't play 'em against pots that don't earn you more than 4.5 to 1.

[toms2866]

A fd with one to come has about 17% chance to hit. $600 pot, $300 to call. You should only call if your implied odds are less than 17%:

17% >= $300 / ($600 + $implied river action)
some algebra...
$implied river action >= $198

Thus, it is only profitable to call if you expect at least $198 in action from your opponent if you hit the flush card on the river. Put another way, you need to be 100% sure he'll call $200 to win a $1100 with a flush card on the board or 50% sure he'll call $400 to win a $1300 pot, etc.

[stevie555]

to make FDs profitable on 4th fold. In my oponion, 2:1 odds on the turn don't justify the implied odds against a random opponent (if you knew he was loose or had a monster hand then situation changes), 2.5:1 is borderline, usually 3:1 is enough to make it +ev.

[Copernicus]

[ QUOTE ]
A fd with one to come has about 17% chance to hit. $600 pot, $300 to call. You should only call if your implied odds are less than 17%:

17% >= $300 / ($600 + $implied river action)
some algebra...
$implied river action >= $198

Thus, it is only profitable to call if you expect at least $198 in action from your opponent if you hit the flush card on the river. Put another way, you need to be 100% sure he'll call $200 to win a $1100 with a flush card on the board or 50% sure he'll call $400 to win a $1300 pot, etc.

[/ QUOTE ]

Just a nit from a mathematician. 17% is not an expression of "odds" it is a probability. They are not the same thing.

[toms2866]

[ QUOTE ]
Just a nit from a mathematician. 17% is not an expression of "odds" it is a probability. They are not the same thing.

[/ QUOTE ]
Yeah, you're right. I'm was just lazy. Everyone knows what "implied odds" refers to, but probabilities were more convenient to work with. The phrase "implied probability" isn't widely used. For anybody who may be confused: x:y odds = x/(x+y) % probability.