# Number Bonds

## What are number bonds?

Number bonds are pairs of numbers that can be added together to make another number e.g. 5 + 5 = 10. They are an important part of maths because they support children in recognising number patterns and developing mental recall. Number bonds can be used to aid mental arithmetic speed and fluency.

## What are number bonds to 5?

Number bonds to 5 are pairs of numbers that can be added together to make 5. Learning number bonds to 5 is often children’s first experience of number bonds. They can be done easily using fingers and involve groups of numbers that are easy to visualise.

Number bonds to 5 include:

0 + 5 = 5

1 + 4 = 5

2 + 3 = 5

3 + 2 = 5

4 + 1 = 5

5 + 0 = 5

## What are number bonds to 10?

Number bonds to 10 are pairs of numbers that can be added together to make 10. Learning number bonds to 10 supports children solving a range of number problems and helps them become familiar with the number system.

Developing a quick recall of number bonds to 10 allows children to begin to understand the concept of partitioning and bridging 10. For example to a solve problem like, 8 + 5 children can partition the 5 into 2 and 3 and then use their knowledge of number bonds to 10. The number sentence 8 + 5 could then be solved like this:

8 + 5

= 8 + 2 + 3

= 10 + 3

= 13

Number bonds to 10 include:

0 + 10 = 10

1 + 9 = 10

2 + 8 = 10

3 + 7 = 10

4 + 6 = 10

5 + 5 = 10

6 + 4 = 10

7 + 3 = 10

8 + 2 = 10

9 + 1 = 10

10 + 0 = 10

## What are number bonds to 20?

Number bonds to 20 are pairs of numbers that can be added together to make 20. Learning number bonds to 20 supports children's fluency with addition when solving a range of number problems.

Number bonds to 20 include:

0 + 20 = 20

1 + 19 = 20

2 + 18 = 20

3 + 17 = 20

4 + 16 = 20

5 + 15 = 20

6 + 14 = 20

7 + 13 = 20

8 + 12 = 20

9 + 11 = 20

10 + 10 = 20

11 + 9 = 20

12 + 8 = 20

13 + 7 = 20

14 + 6 = 20

15 + 5 = 20

16 + 4 = 20

17 + 3 = 20

18 + 2 = 20

19 + 1 = 20

20 + 0 = 20

## What are number bonds to 100?

Number bonds to 100 are pairs of numbers that can be added together to make 100. Learning number bonds to 100 supports childrens fluency with addition when solving a range of number problems.

In order to be able to work out number bonds to 100 children need to have a good understanding of place value.

Number bonds to 100 include:

50 + 50 = 100

30 + 70 = 100

25 + 75 = 100

99 + 1 = 100

0 + 100 = 100