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Finding Perimeter by Counting Units | Math with Mr. J

From Math with Mr. J

Finding Perimeter by Counting Units | Math with Mr. J
7 min3rd4thMath
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Summary

How to find the perimeter of a shape -- the distance all the way around -- by adding the side lengths. Mr. J keeps area and perimeter straight.

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All ages

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Teaching resources

Discussion questions

Perimeter is the total distance around the outside of a shape.

  1. How is perimeter different from area?
  2. How do you find the perimeter of a rectangle quickly?
  3. What units is perimeter measured in?

Quick work-a-long

Words to know: perimeter, side length, distance around

  • Find the perimeter of a 5-by-3 rectangle.
  • Find the perimeter of a triangle with sides 4, 6, and 7.