If there are 8 slices in a large pizza, how many slices will remain if Mary orders 2 large pizzas and eats 7 slices?
The number of total slices of pizza is 8 slices per pizza * 2 large pizzas = <<8*2=16>>16 slices
If Mary eats 7 slices, then 16 - 7 = <<16-7=9>>9 remain
#### 9