The colon (:) is used in math when writing a ratio – a set of numbers that shows relationship between them. A ratio looks like this: 15:1. We might use it in a sentence like this:
When I brew coffee, I use a ratio of 15:1. I use 15 parts of water to 1 part of ground coffee.
Another way to use a ratio is to talk about the chance of something happening.
There is a 1:2 chance that a dropped coin will land heads up.
That means that for every two times you drop the coin, one of those two times will result in the coin landing heads up.
Use the colon to write a ratio.
It’s your turn. Write a sentence with a ratio in it. Be sure to use a colon.