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3rd grade math · Unit 2: Lines, shapes, area, and perimeter

Perimeter around the edge

What this lesson shows

Add the four sides, or double each side and add.

The worked example

The lesson works this one step by step: 7 by 4. Then your kid tries one like it on paper.

The steps

  1. Label all four sides
  2. Add them all
  3. Or double and add
  4. Answer in feet

Helping at home

Label all four sides first: the sides across from each other match. Add all four, or double the length and the width and add. The answer is a length, in feet.

If your kid gets stuck

Label all four sides first.

Watch it with Lux

With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.

See how Lux works

Standards

  • Common Core 3.MD.D.8
    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.
Matches standards in 50 statesSee each state's code

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