When we are asked to **subtract** numbers such as 15 - 5, we can sometimes work out the answer in our heads.

However, when we are given questions with bigger numbers, we might need to use a written method.

In this activity, we'll look at the **columnar method** to **subtract numbers.**

Let's have a look at how we can use the method to subtract:

**66 - 44**

First, we write the numbers in columns** under the correct unit (T = tens, O = ones )**.** **

T O

6 6

__4 4__

We need to write a** subtraction symbol **next to the columns to tell us that we are subtracting in this calculation!

Starting at the right-hand column (ones), we **subtract** the bottom number from the top and write the answers underneath.

T O

6 6

__4 4__

2 2

**66 - 44 = 22**

Here's another example:

H O

7 9

__0 4__

7 5

**79 - 4 = 75**

We must remember to put each digit into the correct column or the answer will be wrong!

In this question, we could put a zero in the tens column if it helps. ** **

Are you ready to have a go at some questions now?