Please don't bet your own money :) If A win gives 1.2x, and B win gives 3x, the betting house probably has the probability of A winning something like 90% of t

Please don't bet your own money :) If A win gives 1.2x, and B win gives 3x, the betting house probably has the probability of A winning something like 90% of the time, and B winning 10% of the time. They want sufficient people to bet on either so that in the full picture, they'd be at net positive whatever happens. That's also why they adjust the winning odds as the bets come in (they don't care about winning big, just winning consistently). However, for an individual bet, you're more likely to keep your money if you go with the 1.2x choice.