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Math 101: What is a Perimeter? What is an Area?

May 4, 2020

You may have heard these terms in your pre-algebra or geometry classes, but let’s do a quick review.

A perimeter measures the distance or length around a shape.  Think of a flat surface, the shape is two-dimensional, meaning it has both a length and width.   Here are some real life examples:

Building a fence around your backyard.  You’ll need to measure how long and how wide it has to be.

Width x length

If your trainer or coach wants to punish you by making you run a lap around the track, that’s 400 meters.  It’s also an Olympic event.


You may recognize these formulas for a couple common shapes:


Width x length rectangle


Width x length Square

The area is how much space the inside of the shape takes up.  Examples include:

If you’re painting a mural, it’s determining how much of the wall you’re going to paint.


If you have to mow a whole football field, it’s figuring out how big that field is.

Football Field

Here’s a couple formulas for area:


Width x length Rectangle


Width x length Square

These aren’t the only formulas for perimeter and area; there are shapes like circles and triangles and trapezoids oh my! 

If you made it to the end of this blog, congrats! Let us know if there are other math topics you’d like us to cover. We are here to help you succeed. 

Gary D. Marketing Director by day, math teacher to a 17 year old by night.  
Loves air conditioning. Hates carbs.
Keeps receipts.


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