Unit 2 Contents

Fact Families

1. The picture below models the following problem: If a rectangle has a total of 20 squares organized in 4 rows, how many squares are in each row?

What division sentence describes this problem?

2. The picture below models the following problem: If a rectangle has a total of 20 squares organized in 5 rows, how many squares are in each row?

What division sentence describes this problem?

3. What do you notice about the rectangles in Questions 2 and 3? (Draw both of these rectangles on a piece of Centimeter Grid Paper. Cut them out and lay one on top of the other.)
4. What two multiplication sentences describe the two rectangles in Questions 1 and 2?

The four facts below are related facts. We say they are in the same fact family.

4 5 = 20  5 4 = 20  20 ÷ 4 = 5  20 ÷ 5 = 4