Lesson 10

This lesson builds on students’ work on area and fractions in grade 5. Students solve problems involving the relationship between area and side lengths of rectangles, in cases where these measurements can be fractions. Knowing that the area of a rectangle can be found by multiplying its side lengths, and knowing the relationship between multiplication and division, they use division to find an unknown side length when the other side length and the area are given.

Then, they extend their work on area to include triangles, using division to find the length of a base or a height in a triangle when the area is known.

Consider having the objects mentioned in the How Many Would it Take? activity available for students to verify their answers. These objects are: \(\frac34\)-inch square stickers, \(\frac58\)-binder clips, and \(1\frac34\)-inch paper clips.