What is a ratio in its simplest form?

A ratio written in its simplest form is a ratio of whole numbers that cannot be further divided.

24 : 60 = 2(3)(4) : 3(4)(5) = 2 : 5

A ratio in its simplest form is a ratio where you cannot find a common factor of all the parts other than one to divide by.

SImplifying a ratio into its simplest form is very similar to how we simplify fractions. We take the numbers in to the given ratio such as 15:10 and find the highest common factor (the biggest number that goes in to 15 and 10) and divide both numbers by that value.

In this case the highest common factor of 15 and 10 is 5.

When we divide both of these numbers by 5 we end up with 3:2 as our ratio in its simplest form.

It's also worth mentioning that sometimes we can't always find the highest common factor if the numbers are quite large. In a case of 80:56 we might find it easier to simplify in steps.

Both numbers can be divided by 2 so we could simplify it down to 40:28 and then keep dividing it by 2 to get 20:14 and then 10:7. At this point we can't divide by any more numbers so 10:7 would be the ratio in its simplest form.