Example 10 outs:47 unseen cards. With 2 to come there are 47*46/2*1 combinations of cards=1081. Chance of hitting your card twice = 10*9/2*1=45 ways. Chances of hitting your card once( hit/miss combo)is 10 hits * 37 miss(47cards-10 hits)=370. Add 370 hit/miss combos + 45 Hit/Hit combos =415. Odds =1081 Total-415 (combinations which include at least one of your outs):415 or 1081-451:415=666:415 = 1.6:1