Number bonds to 100

Number bonds are pairs of numbers that add up to a target number.

Number bonds to 10 can be described in different ways. You can say '6 and 4 make 10', or '3 and 7 more equal 10', or even that 'double 5 is 10'.

This diagram shows the connection between the numbers that form number bonds to 10.

Number bonds to 100 are pairs of numbers that when added together make 100.

You can use your knowledge of number bonds to 10 to find number bonds to 100.

There are many different combinations of numbers that make 100. The greater the number, the more number bonds it will have!

Complete this interactive activity to better understand number bonds to 100. Then put your knowledge to the test.

Number bonds are numbers that come in pairs. They add up to a target number, like 10.

Knowing your number pairs to 10, will make it easier to work out your number pairs to 100. For example:

1 + 9 ‎ = 10

10 + 90 ‎ = 100

Can you see the link between pairs that make 10 and pairs that make 100?

A number line can help you find more tricky number pairs to 100.

For example, here is the number line with the number 63 marked on it.

Let's use it to find which number forms a number bond to 100 with 63?

You can start by jumping from 63 on to the next multiple of ten, which is 70.

64 to 70 is a jump of 2.

Next you jump on from 70 to 100, which is a jump of 30.

You then add the small jump and the big jump together.

7 + 30 ‎ = 37

So 63 and 37 are a number pair. You can check your answer by adding the two numbers together.

63 + 37 ‎ = 100

Example 2

Example 3