Arithmetic Grade Four

Lesson One hundred and sixty-eight: Perimeter


Perimeter is the distance around a shape. Consider this triangle:

As you can see it has three sides which are 13, 10, and 16 units long. To find the total distance around this object you simply add up the length of each side.


   PERIMETER = 13 + 10 + 16 = 39 units

Remember units can be inches, feet, yards, meters, or any other unit of length. We use the term units when the actual unit is left unspecified.


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