Answer:the answer is 2.50.
Explanation:
He buys 2 snacks that is 1.55. You need to ADD both of those. When you do that, you get 3.10. He also bought a lumch combo for 7.50. You need to ADD 3.10 and 7.50. After adding those you need to subtract the total amount of money he had (13.10) and the total amount he used (10.60) When you subtract them, you get the answer of 2.50.