Lesson: Perimeters of Rectangles with the Same Area Mathematics • 3rd Grade

In this lesson, we will learn how to draw rectangles with the same area using unit squares, count to find their perimeter, and compare these perimeters.

Lesson Plan

Students will be able to

recognize that rectangles can have the same area but different dimensions and perimeters,
compare the perimeters of rectangles with the same area but different dimensions,
explain the difference in perimeter between rectangles with the same area,
construct different rectangles with the same area.

Lesson Video

Lesson Worksheet

Q1:

True or False: Rectangles can have the same areas but different perimeters.

Q2:

Here are two rectangles with the same area. Which of them has the largest perimeter?

Q3:

Here are two rectangles.

True or False: Both rectangles have the same area.

True or False: Both rectangles have different perimeters.

Which rectangle has the smallest perimeter?