*This quiz addresses the requirements of the National Curriculum KS1 Maths and Numeracy for children aged 5 and 6 in year 1. Specifically this quiz is aimed at the section dealing with representing and using number bonds and related subtraction facts within 20.*

As part of learning about addition and subtraction, children in Year 1 will learn about pairs of numbers which add together to make twenty. These are known as number bonds to twenty and are useful when calculating quickly. Once the addition facts, or number bonds, are learnt by heart, children may then learn the associated subtraction facts. For example, if 17 + 3 = 20, then 20 - 3 = 17 or 20 - 17 = 3.

Question 1

Which set is correct?

9 + 18 = 20, 18 + 9 = 20, 20 - 18 = 9, 20 - 9 = 18

12 + 11 = 20, 11 + 12 = 20, 20 - 11 = 12, 20 - 12 = 11

15 + 7 = 20, 7 + 15 = 20, 20 - 15 = 7, 20 - 7 = 15

19 + 1 = 20, 1 + 19 = 20, 20 - 1 = 19, 20 - 19 = 1

For the subtraction facts, 20 always comes at the beginning of the calculation

Question 2

Which set is correct?

15 + 6 = 20, 6 + 15 = 20, 20 - 15 = 6, 20 - 6 = 15

11 + 9 = 20, 9 + 11 = 20, 20 - 9 = 11, 20 - 11 = 9

13 + 17 = 20, 17 + 13 = 20, 20 - 13 = 17, 20 - 17 = 13

14 + 9 = 20, 9 + 14 = 20, 20 - 9 = 14, 20 - 14 = 9

The four facts are all related to each other

Question 3

Which number is added to 10 to make 20?

19

10

20

2

10 + 10 = 20

Question 4

Which of the following is not a number bond to 20?

17 + 3

2 + 18

19 + 4

11 + 9

19 + 4 = 23, not 20

Question 5

Which of the following is not a number bond to 20?

15 + 5

18 + 3

20 + 0

1 + 19

18 + 3 = 21, not 20

Question 6

Which number is added to 14 to make 20?

24

10

4

6

14 + 6 = 20

Question 7

20 - 8 = ?

15

12

8

11

8 + 12 = 20, so 20 - 8 = 12

Question 8

What is a number bond to 20?

Numbers which are on a number line

A strong number less than 20

A pair of numbers which add up to 20

A number which can be added to 20

A number bond is a pair of numbers which add to give a target such as 20

Question 9

If 6 + 14 = 20, then...

20 - 6 = 14

6 - 20 = 14

14 - 20 = 6

6 - 14 = 20

20 - 6 = 14 is one of the subtraction facts for 6 + 14 = 20

Question 10

If 13 + 7 = 20, then...

7 - 13 = 20

13 - 7 = 20

13 - 20 = 7

20 - 13 = 7

20 - 13 = 7 is one of the subtraction facts for 13 + 7 = 20