How do you calculate the payoff on a Trifecta at a pari-mutuel Horse Track?

Generally: Take the total amount wagered in the trifecta pool and multiply it by the takeout rate (a.k.a. commission rate). Subtract this amount from the total amount wagered in the pool. From the amount remaining (the Net pool), subtract the amount of money that was placed on the winning Trifecta combination, leaving you with the Profit pool. Divide the Profit pool by the amount that was bet on the winning combination. Add 1 to the division's resulting amount. Drop the pennies so you're left with the dollars and dimes. This is the payout (price) amount on the winning combination per $1 of winning money.