20 Sep

Calculate the Area of a Compound Shape

Area of a Compound Shape

Have you ever needed to learn how to calculate the area of a compound shape?

Let Key Stage 2 Maths help you with our online video tutorial explaining how to calculate area and how you can use it specifically when calculating the area of a compound shape.

Solve common compound shape calculation problems today!

Compound Shape

A compound shape is the result of two or more simple shapes placed beside each other. An easy to understand example is two rectangles placed together to form an “L” shape.

Compound Shape Example

Calculate Area

There will always be instances within Key Stage 2 Maths where you need to work out the area of a compound shape.

Now, what you need to do is look at your shape and you need to split it into rectangles. I’m going to draw a line here and we have rectangle A and rectangle B.

Compound Shape Example A and B

To calculate the area of a compound shape you need to know the Length and the Width because these are multiplied together to equal the Area.

Calculate Area of Shape A

For shape A you already have a Length and a Width (it’s not to scale!) but you already have it. 3cm times 3cm equals 9cm squared – that was pretty simple!

3cm x 3cm = 9cm²

Calculate Area of Shape B

However, shape B you’ve only got one measurement – 10cm times something equals something. What you need to do is to use the figures that you already have to calculate the missing Width.

The numbers that you’re going to be looking at are the numbers which are parallel to the line which has a missing width. This is parallel and so is that.

If that length from start to end equals 3cm then so must that part for that whole entire length. All together, that length from here to here equals 5cm. So if that is 3cm, then you must add 2cm to that to make 5cm.

10cm x 2cm = 20cm²

You’ve just figured out using the parallel lengths that of the missing length.

Answer: 29cm²

Our 3 minute video will cover all that you need to know to calculate the area of a compound shape from a Key Stage 2 Maths perspective.

About the author

Tina Mavadia Primary school teacher who has worked throughout London and Hertfordshire. Add Tina Mavadia to Google Plus or check out my Key Stage 2 Maths channel on YouTube.

10 thoughts on “Calculate the Area of a Compound Shape

  1. This is not helpful. I mean all it is showing is how to do simple figures! I have a really complex problem I need help with but this does not help or show me anything!!!!!!!

  2. This is an excellent video with good explanation to match. It was just one of many useful resources that I used with a 10 year old student this morning. Thank you

  3. Not helpful doing more numbers than one its 8 numbers on the compound figure and in 6th grade and thats wrong you suppose to multiply 3×3 which is 9 and 10×5 which is 50 so im trying to figure out where did 2 come from

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