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Home > Maths > Measures > Perimeter




Simple shapes

The perimeter of a shape is the length of its boundary.

Think of an ant starting from one corner of a small box, measuring 3 cm by 4cm. Imagine it walks all the way around the edge of the box. What distance will it have walked?

A box with 2 sides measuring 4cm wide and 2 sides measuring 3cm tall.

Perimeter = 4 + 3 + 4 + 3 = 14 cm

When calculating the perimeter, remember to include the length of every side.


Perimeter activity

Struggling to find you way around? Try this activity.



Can you conquer the elements?

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