Learn how to find a common factor, the highest common factor (HCF) and lowest common multiple (LCM) as well as what a common factor is with in this KS3 guide.

They are the multiplication “facts” of the number. A common factor is a factor that is shared by two or more numbers. The number 1 will be a common factor for every single number!

A common factor is a number that can be divided into two different numbers, without leaving a remainder. Find out in this KS3 Bitesize Maths guide.

is found by finding all common factors of two numbers and selecting the largest one. For example, 8 and 12 have common factors of 1, 2 and 4. The highest common factor is 4.

Practise what you've learned about Highest Common Factor and Lowest Common Multiple with this quiz. The quiz questions change each time you play, so keep testing your knowledge.

To find the HCF, find any prime factors that are in common between the products. Each product contains two 2s and one 3, so use these for the HCF. HCF = 2 × 2 × 3 = 12

Factorising means rewriting a maths expression using brackets. Revise how to factorise using the highest common factor in this BBC Bitesize maths guide for KS3.

The highest common factor (HCF) is found by identifying all common factors of two numbers and selecting the largest one. For example, 8 and 12 have common factors of 1, 2 and 4.

Highest common factor is written as HCF. . The ratio 10 : 4 simplifies to 5 : 2, for example. To simplify ratios, knowledge of how to find the highest common factor (HCF) is useful.

What is a factor and what is a multiple? Use the concepts and vocabulary of factors and multiples. Find all the factor pairs for a number in this Bitesize Maths guide.