Factors of 20

Step by step

The question

Question: find the factors of 20.

A factor of 20 is a whole number that goes into 20 exactly.

Nothing is left over.

1 Find the factor pairs

We start with 1.

1 goes into every number: 1 times 20 is 20.

Each number that goes in comes with a partner.

20 divided by 2 is 10.

Nothing is left over.

So 2 times 10 is 20.

Does 3 go in?

20 divided by 3 is 6, with 2 left over.

So 3 is not a factor.

20 divided by 4 is 5.

Nothing is left over.

So 4 times 5 is 20.

Next is 5.

But 5 times 5 is 25, more than 20.

From here the pairs only repeat.

So we stop.

2 List them in order

Now we write them from small to big.

First the orange numbers, going down.

Then the purple numbers, going up.

So 20 has 6 factors: 1, 2, 4, 5, 10 and 20.

Let's look back.

First: find the factor pairs.

Last: list them in order.