Decompose Shapes to Compare Areas

Videos, examples, solutions, and lessons to help Grade 3 students learn how to decompose and recompose shapes to compare areas.

Common Core Standards: 3.MD.5, 3.MD.6, 3.MD.7

New York State Common Core Math Module 4, Grade 3, Lesson 2

Application Problem

Wilma and Freddie use patterns blocks to make shapes as shown. Freddie says his shape is bigger than Wilma’s because it’s longer than hers. Is he right? Explain your answer.

Note: This problem reviews Grade 3–M4–Lesson 1, specifically that even though shapes look different, they can have the same area.

Concept Development

Rearrange 12 square tiles to make different rectangles.

Lesson 2 Homework

1. Each □ is a square unit. Count to find the area of each rectangle. Then circle all the rectangles with an area of 12 square units.

2. Colin uses square inch pieces to create these rectangles. Do they have the same area? Explain.

3. Each □ is a square unit. Count to find the area of the rectangle below. Then draw a different rectangle that has the same area.

Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

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