Perimeter is the measurement of length around a shape. You can think of it as a boundary or fence around your “geometric” yard.
Author
Michelle Griczika
Published
January 2024
Perimeter is the measurement of length around a shape. You can think of it as a boundary or fence around your “geometric” yard.
Author
Michelle Griczika
Published
January 2024
Perimeter is the measurement of length around a shape. You can think of it as a boundary or fence around your “geometric” yard.
Author
Michelle Griczika
Published
January 2024
Key takeaways
Table of contents
When you think of the outline of a shape or the boundary that encloses its space, you’re thinking of the perimeter. It’s the total distance around the edges of a geometric figure. This concept is crucial in maths for helping us measure and compare different shapes.
Perimeter refers to the total distance around a shape. It’s like tracing the edges or boundaries of a figure to measure its full length. In simpler terms, imagine tying a string around a shape; the length of that string represents the perimeter.
There are many uses for finding perimeter in everyday life. Calculating perimeter is especially important in construction or sports like distance running. Here are some real life scenarios where you may need to know the perimeter:
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Understanding perimeter involves knowing how to measure the distance around different shapes. Each shape has its unique formula to find the perimeter. Let’s look at a few of the common shapes and their formulas:
Here’s a handy table with all the perimeter formulas for a quick look:
Shape | Formula for Perimeter |
Square | P = 4s (where s = length of one side) |
Rectangle | P = 2(l + w) or P = 2l + 2w |
Circle | P = 2πr |
Triangle | P = a + b + c |
Parallelogram | P = 2(a + b) or P = 2a + 2b |
Trapezium | P = a + b + c + d |
Remember, knowing the formula is just the start. Applying it practically helps strengthen your understanding. Dive deeper with our maths app for more practice on perimeter calculations.
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How do you find perimeter? To find out how long the outside of a shape is, follow these steps:
These are easy shapes like squares, circles, and rectangles.
Here’s what to do:
For trickier shapes, try this:
In short, figure out the shape, use the right maths, and you’ll get your answer. And remember, the formula table is super helpful!
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Click on the boxes below to see the answers!
Rectangle: 36 units
Square: 32 units
Triangle: 18 units
Circle: 25.12 units
Parallelogram: 30 units
Trapezium: 34 units
Rectangle: 44 units
Square: 24 units
Triangle: 30 units
Circle: 31.4 units
Perimeter refers to the total distance around a shape. It measures the boundaries or edges of a figure.
To find the perimeter, you add up the lengths of all the sides of the shape. For certain regular shapes like rectangles or circles, specific formulas can be applied.
The perimeter of a rectangle is found by adding up all its sides, which includes twice the length and twice the width or 2(l + w).
Area measures the total space inside a shape, while perimeter measures the total distance around it.
Parents, sign up for a DoodleMaths subscription and see your child become a maths wizard!
Lesson credits
Michelle Griczika
Michelle Griczika is a seasoned educator and experienced freelance writer. Her years teaching coupled with her double certification in early childhood education lend depth to her understanding of diverse learning stages. Michelle enjoys running in her free time and undertaking home projects.
Michelle Griczika
Michelle Griczika is a seasoned educator and experienced freelance writer. Her years teaching coupled with her double certification in early childhood education lend depth to her understanding of diverse learning stages. Michelle enjoys running in her free time and undertaking home projects.
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