Complete the Subtraction: Numbers up to 20

Subtraction is taking something away.

You can use subtraction to find missing numbers. You do it like this.

 

Example

Count the top row of chicks. There are 10.

Take 2 chicks away.

 

What's the difference? (How many are left?)

 

subtract

 

Answer: 8

10 - 2 = 8

 

You can use a number line to help you with subtraction.

Start at the number 10 on the line and move two places to the left on the line.

You reach the number 8. So you can see that 10 - 2 = 8

 

 

You always move to the left on a number line when you are subtracting a number.

 

 

Let's have a go at some questions now.