Videos and lessons to help Grade 3 students learn to solve real world and mathematical problems involving perimeters of polygons, including finding the perimeter given the side lengths, finding an unknown side length, and exhibiting rectangles with the same perimeter and different areas or with the same area and different perimeters.

Common Core: 3.MD.8

- I can identify polygons.
- I can define perimeter.
- I can find the perimeter of polygons when give the lengths of all sides.
- I can find the unknown side lengths of polygons when given the perimeter.
- I can show how rectangles with the same perimeter can have different areas and show rectangles with the same area can have different perimeters.
- I can solve word problems.

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More Lessons for Grade 3

Common Core for Grade 3

Solve real-world and mathematical problems involving perimeters of polygons--Lesson 1 of 7 (3.MD.8)

In this lesson, you will learn how to find the perimeter of a polygon by using grid paper.

Solve real-world and mathematical problems involving perimeters of polygons--Lesson 2 of 7

In this lesson, you will learn how to find the perimeter of a square or rectangle by adding the side lengths.

Solve real-world and mathematical problems involving perimeters of polygons--Lesson 3 of 7

In this lesson you will learn how to find the perimeter of a polygon by solving real world problems.

Example: If her garden is a square with an area of 36 square meters and one side is 6 meters long, how much fencing does Mrs. McArthur need to purchase?

Solve real-world and mathematical problems involving perimeters of polygons--Lesson 4 of 7

In this lesson, you will learn how to find the perimeter of a square or rectangle with a missing side length by using square tiles.

Solve real-world and mathematical problems involving perimeters of polygons--Lesson 5 of 7

In this lesson, you will learn how to find the perimeter of a polygon with more than 4 sides by adding the side lengths.

Solve real-world and mathematical problems involving perimeters of polygons--Lesson 6 of 7

In this lesson you will learn that rectangles can have the same perimeter but different area by building rectangles and organizing information in a chart.

Solve real-world and mathematical problems involving perimeters of polygons--Lesson 7 of 7

In this lesson you will learn that rectangles can have the same area but different perimeter by building rectangles and organizing the information into a chart.

3 MD 8 Lesson 1

In this lesson, you will learn how to determine the perimeter of a polygon by adding the side lengths.

3 MD 8 Lesson 2

In this lesson, you will learn how to find unknown side lengths of polygons given the perimeter.

3 MD 8 Lesson 3

In this lesson, you will learn how to find an unknown side length of a rectangle given the perimeter.

Finding the perimeter of Squares and Rectangles- 3.MD.8

Find Unknown Side Given Perimeter - 3.MD.8

Perimeter of Polygons.

Perimeter of Polygons

Learn to compute perimeter of polygons.

Find the Missing Side of a Polygon

Learn to find the missing side of a polygon.

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