Answer:
Tony's addition is correct.
Explanation:
Tony needs to add 7 two times, since the customers ate 7 slices of out both pizzas. And, 7 + 7 is 14, and you need to also count the total slices of pizza, which is 16. So, the fraction would be 14/16, which can be simplified into 7/8, which is just 14/16 multiplied by 2.