Highest Common Factor Worksheets 18: Find the highest common factor (HCF) of each number pair. Click the button below to try all our FREE online, PDF, or printable Greatest Common Factor worksheets.

Try all Highest Common Factor worksheets!

Click to read the Short Note

What are factors?

The two numbers that we multiply together to get a multiple are called **factors**.

Factor x Factor = Multiple

**4 x 7 = 28**

What are common factors?

When you list the factors of two or more numbers (or multiples), sometimes you can see some factors are in all the lists of factors. These factors which appear in all the lists of factors are called **common factors**.

What is Highest Common Factor (HCF)?

The largest common factor of a list of common factors is called the **Highest Common Factor**. In short we call it **HCF**.

Highest common factor (HCF) is also known as the **Greatest Common Factor (GCM)**.

Follow the example below to find the highest common factor (HCF) or the greatest common factor (GCF) of a number pair.

**Find the highest common factor (HCF) of 24 and 32**

**Example 1:**

Step 1:

Find the factors of 24

**1**, **2**, 3, **4**, 6, **8**, 12, 24

Step 2:

Find the factors of 32

**1**, **2**, **4**, **8**, 16, 32

Step 3:

Group the common factors

**1, 2, 4, 8**

Step 4:

Find the highest factor of all the common factors

**8** is the highest factor of all the common factors of 24 and 32

Therefore 8 is the highest common factor of 24 and 32

**Example 2:**

Find the highest factor, which is common to both numbers that each number is divisible by.

This factor is the highest common factor of the number pair.

__24__

32

÷

÷

8

8

=

__3__

4

Therefore the highest common factor of 24 and 32 is 8.

Hit the ‘Check Answers’ button at the end to correct your answers.