Question

Pierre's parents ordered some pizzas for a party. 4.5 pizzas were eaten at the party. There were at least 5 1/2 whole pizzas left over. How many pizzas did pierre's parents order?

Answer 1

Let's convert everything to decimals so that we're not flipping through fractions and decimals.
5 1/2= 5.5
Since 4.5 was eaten but there is 5.5 left, that shows what happen with the total amount of pizzas. So by just adding them, you can find how much pizzas are there in total.
5.5+4.5=
9+1=
10
There were 10 pizzas ordered by Pierre's parents.