What is a common factor?

  • A common factor is a number that can be divided into two different numbers, without leaving a remainder.

  • Often numbers can share more than one common factor.

  • It is possible to find the common factors of more than two numbers.

Find out how to work out the common factors of two numbers using eggs!

What is a common factor?

A factor is a number that divides into another number exactly. To find the common factors of two numbers, you first need to list all the factors of each one and then compare them.

If a factor appears in both lists then it is a common factor.

For example, the factors of 8 are:

1, 2, 4 and 8

The factors of 12 are:

1, 2, 3, 4, 6 and 12

Therefore, the common factors of 8 and 12 are:

1, 2, and 4

Common factors quiz

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Where next?

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