How do you calculate over under?

Over/Under Bet Payouts If you bet $100 on the over, you would win because 86+84=170. 170 is greater than 165.5, so the over wins. You would be paid out at -110 which would net you a profit of $90.91. If you bet the under and the score was under 165.5, you would be paid out the exact same amount for your bet.