Number bonds to 20
Mental Mathematics
Starters
Activity 5
Mathematics Objective
Know by heart all
addition and
subtraction facts
for each number to
20.
Using this should help you learn:
To remember number
bonds to 20 so you
can quickly answer
questions correctly.
Target = 15 out of 20
1. Write the missing number:
3+4=
5+=9
2. Write the missing number:
7+4=
6 +  = 12
3. Write the missing number:
9 +  = 14
15 -  = 9
4. Write the missing number:
6+7=
-8=9
5. Write the missing number:
6 +  = 12
 + 7 = 19
6. Write the missing number:
 + 2 = 11
10 +  = 16
7. Write the missing number:
6 +  = 19
5+9=
8. Write the missing number:
3 + 14 = 
18 -  = 7
9. Write the missing number:
13 + 7 = 
9 +  = 20
10. Write the missing number:
13 + 4 = 
13 -  = 9
11. Write the missing number:
7+7=
8 +  = 19
12. Write the missing number:
 + 8 = 11
12 +  = 20
13. Write the missing number:
17 +  = 20
20 -  = 9
14. Write the missing number:
15 + 2 = 
17 - 9 = 
15. Write the missing number:
8+8=
19 +  = 19
16. Write the missing number:
2 + 16 = 
9 +  = 16
17. Write the missing number:
20 +  = 20
20 -  = 7
18. Write the missing number:
3+4=
5+=9
19. Write the missing number:
3+4=
5+=9
20. Write the missing number:
3+4=
5+=9
Evaluation . . . Did you:
Answer at least 15
out of the 20
questions
correctly?