He would receive $79.99. You start off with 17.01, then add 5, then add 2, then add 3. Now you have 27.01. 27.01 is the amount he needs to pay. Since he is redeeming money from two tickets, add 5 and 2, that gives you 7. But he is paying with a 100 bill, you'll add 7 to that and then you have 107. 107 - 27.01 is 79.99. Unless you don't add the redeemed money then the change is $72.99.