I dont like math, you can do nothing if what card comes up next in Turn and River. Therefore I can say if you have flush draw on the flop or straight draw on the flop, 52 cards in a deck including the dealt cards, just count your outs, if you believe will come out, so be it..and if you feel you get lucky seize the day!
Example in a Tournament, one player accidentally exposed his folded one card (8h), and you hold 8,8, and one player goes all in with a better image on him but folding pocket eights is a tough decision(heads up). The problem is you only have one outer to get a strong hand if ever he's ahead of you.But despite of it you still gamble pocket eights as you feel thats your lucky and believe you wil win that hand and the board goes 5,7,A,6,9 against AA. All I can say is, Thats poker! No assurance at all. Even you fully know about poker calculations you can do nothing if will come out or not, unless you have great skill of bluffing.