Faye bought 3 pizzas. Each pizza has 10 slices in it. If 90% of the lunch was eaten, how many slices are left?

Answer 1

90% = 90/100 = 9/10
So, if 9 out of the 10 slices of a pizza were eaten, how many slices are left
from each pizza?
How many pizzas were there?

Answer 2

3pizzas * 10slices/pizza = 30 slices,
30 - -9*30 = 3 slices left.