Ratio

A ratio is used to compare two quantities. The quantities should be in the same units.

Example

A farmer has \(3\) cats and \(7\) dogs.

Write down the ratio of cats to dogs and the ratio of dogs to cats.

Cats : Dogs = \(3 : 7\)

Dogs : Cats = \(7 : 3\)

Question

The same farmer also has \(85\) sheep and \(15\) cows.

Write down the ratio of cows to sheep in its simplest form.

cows : sheep = \(15 : 85\)

\(15\) and \(85\) are both divisible by \(5\)

\[\frac{{15}}{5} = 3\]

\[\frac{{85}}{5} = 17\]

So \(15 : 85 = 3 : 17\)