Originally Posted by frnandoh
This can be used in any hand, but I have ilustrated with pockets because many people ask about it. If you have A2, how is your chance of hitting an ace on flop? A= 3 outs x 3 cards x 2% = about 18% on flop and 30% regarding all streets (not wall street... why do I mention it?).
This can be used when yo want to know if you can call with expeculative cards or not.


This is not the way to calculate the odds of hitting the flop.
Your odds of hitting an Ace on the flop are 1(47*46*45)/(50*49*48). That is 17.27% of the time. The odds for hitting it on any street? 1(47*46*45*44*43)/(50*49*48*47*46) = 27.6%. Sure, your method will give you an approximate idea, but the reasoning behind it is not correct and will cause issues when people try and reason about more complicated situations (the odds of flopping a flush draw, for example).
This becomes more apparent when talking about things like AK and hitting either card. You say 36% on the flop, the actual amount is 32.4%. Your method gives 60% across all streets. The actual number is 48.7%, which is a big difference. Your method consistently overestimates flop equity.