How_To_Be_Good_At_Math

and perimeter Comparing area

Comparing area

and perimeter

We know how to find the area and perimeter of shapes,

but how are they related? If two shapes have the same

area, they don’t always have the same perimeter. This is

true the other way round, too.

The perimeter of the

penguin enclosure is 64 m.

This is greater than the perimeter

of the zebra enclosure, even

though the area is the same.

The tortoise enclosure has

an even greater perimeter.

Its perimeter is 68 m.

Same area but

different perimeter

Look at these three zoo enclosures.

They all have the same area – 240 m².

Does this mean that they all have the

same perimeter too?

15 m

12 m

10 m

16 m

Perimeter = 62 m

Area = 240 m²

Perimeter = 64 m

Area = 240 m²

Perimeter = 68 m

Area = 240 m²

20 m

24 m

If we look at the zebra

enclosure, we can see that

it has a perimeter of 62 m.

Even if shapes have the same

area, they may not have the

same perimeter. Also, shapes

with the same perimeter may

not have the same area.

It’s important to remember

that even if shapes have

the same area, they may not

have the same perimeter.

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