Calculating Pot Odds is a habitual operation for poker players. Once you play, you should be able to maintain it in seconds.
Suppose you dont nave a made hand at the beginning of the game. To decide whether to fold or not you must use 'pot odds'. First of all count the number of your outs that is the amount of unseen cards, which can improve your hand. For example, if you have KJ, and the board is Q 10 7, then your outs are 4 Aces and 4 Nines. So you have 8 outs.
Now let us calculate your chances to win. If they are 5-to-1 or better you can call. Otherwise the best variant for you is to fold. We should divide the number of all unseen cards, useless for you, by the amount of your outs. There are 47 unseen cards. 8 of them would help you, while the rest would not. In our case that will be 39/8 = 4.875 and your chances to win are 4.875-to-1 which is bigger than 5-to-1. So dont be afraid and call.
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