What is a ratio? A ratio is a number that compares values. Imagine you are making fruit juice and need three apples for every orange to make one cup of juice. If you have three apples and one orange, then you have a ratio of 3 apples to every 1 orange. The ratio would be written as 3:1. If you want to make more juice, you can use the ratio to decide how many ingredients you need. Say you want two cups of juice. You can add one orange to your recipe (for a total of 2 oranges). The ratio of 3 apples to 1 orange means you would then need 3 more apples (for a total of 6 apples), leading to a ratio of 6:2. So 3:1 is also 6:2.
A golden ratio is a special ratio. In the golden ratio, a whole is broken into two unequal parts where the whole number divided by the larger part equals the larger part divided by the smaller part. That might sound a bit confusing, so let's look at an example.
Imagine we snap a ruler that is 100 centimeters long into two pieces. The two pieces are not equal.

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