Answer:
2 and a half pizzas were eaten
Explanation:
3 pizzas divided into 8 slices is equal to 24 slices. So if 20 slices were eaten, we can do simple math to solve this
There are two ways to do this:
A. divide 20 by 8 to get 2.5
B. subtract a pizza (8 slices) from 20 to get 12. Subtract another pizza (8 more slices) to get 4. The 4 slices left are equal to another half pizza. So in total, there were 2.5 pizzas eaten