A shortcut to calculating your percentage chance of hitting one of your outs on the next two cards. Multiply the number of outs x 4 and this gives you the percentage chance of hitting one of your outs on the next two streets. For example, you have 2 outs to hit a set on the turn or river. Multiply 2 x 4 to get a result of 8. This means you have an 8% chance of hitting on the next 2 cards to come. Use this rule only in a situation where you are all in on the flop and guaranteed to see the turn and river cards.