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Ratio

Ratios are one way of comparing amounts of things. Ratios can tell us how much bigger, or smaller, one thing is than another. In other words, ratios show how much of one thing we have in relation to another thing.

In this Ratio and Proportion section you will find additional guidance on direct proportion, help with simplifying ratios, and guidance on using ratio and proportion.

Note: You can also get to these pages by using the menu towards the top of this page.

Example of ratio

In the example below we are trying to get purple paint by mixing cans of red and blue paint.

4 parts blue paint
3 parts red paint

The ratio of blue to red paint is 4:3

Writing ratios

There are three ways that ratios are commonly written:

  1. in words e.g. 4 to 3
  2. with a colon (odds notation) e.g. 4:3
  3. fractional notation e.g. 4/3

Watch the words, numbers, and order in ratios

When writing ratios be careful to write the numbers in the same order as the words (or things) to which they refer.

A ratio of 4:3 is not the same as a ratio of 3:4

Identifying Ratios Worksheets

You will find more ratio and proportion worksheets here

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