Part of Mathematics and Numeracy2d shapesYear 3Year 4
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The perimeter is the distance all the way around the outside of a 2D shape.
To work out the perimeter, add up the lengths of all the sides.
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How far are you going to walk today?
So you're going to walk all around the outside of the park?
The outside edge of a shape is called the perimeter.
It's easy to know how far you're going to walk.
We just measure the perimeter.
How many steps does it take you to walk along the first side?
10 steps. Right. And how many steps does it take to walk around the next side?
6 steps. Ok. Now do the next side.
10 steps again, yes.
And now back to where you started.
All we need to do is add the numbers from each of the sides together and then we know how far it is all the way around.
So 10 + 6 + 10 + 6 equals 32.
You'll walk for 32 steps if you go all the way around the perimeter.
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