For those of you new to the odds game, the favorite will have a negative (-) number, while the underdog will have a positive (+) number. MMA money lines are based on units of $100. If the favorite is -225, it means that you have to wager $225 to win $100. But if you are betting on the underdog, the formula is different. If the underdog is at +185, it means that if you wager $100 you will win $185 for a total of $285. Easy enough, right? Good.