MathsAges 7-9

Complements to 10, 20 & 100

Find how many more are needed to complete a benchmark number such as 10, 20, 50 or 100. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

1. How many more do you need to add to 11 to make 100?
11 · 100 · Complements to 10, 20 & 100
2. How many more do you need to add to 11 to make 30?
11 · 30 · Complements to 10, 20 & 100
3. How many more do you need to add to 33 to make 50?
33 · 50 · Complements to 10, 20 & 100
4. How many more do you need to add to 11 to make 50?
11 · 50 · Complements to 10, 20 & 100
5. How many more do you need to add to 9 to make 30?
9 · 30 · Complements to 10, 20 & 100
6. How many more do you need to add to 13 to make 30?
13 · 30 · Complements to 10, 20 & 100
7. How many more do you need to add to 15 to make 20?
15 · 20 · Complements to 10, 20 & 100
8. How many more do you need to add to 24 to make 50?
24 · 50 · Complements to 10, 20 & 100
9. How many more do you need to add to 30 to make 100?
30 · 100 · Complements to 10, 20 & 100
10. How many more do you need to add to 9 to make 20?
9 · 20 · Complements to 10, 20 & 100
11. How many more do you need to add to 96 to make 100?
96 · 100 · Complements to 10, 20 & 100
12. How many more do you need to add to 12 to make 20?
12 · 20 · Complements to 10, 20 & 100

12 questions · Seed 104776 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 7-9

Answers and reasoning. Review before teaching.

1. How many more do you need to add to 11 to make 100?
89
Subtract 11 from 100: 100 − 11 = 89.
2. How many more do you need to add to 11 to make 30?
19
Subtract 11 from 30: 30 − 11 = 19.
3. How many more do you need to add to 33 to make 50?
17
Subtract 33 from 50: 50 − 33 = 17.
4. How many more do you need to add to 11 to make 50?
39
Subtract 11 from 50: 50 − 11 = 39.
5. How many more do you need to add to 9 to make 30?
21
Subtract 9 from 30: 30 − 9 = 21.
6. How many more do you need to add to 13 to make 30?
17
Subtract 13 from 30: 30 − 13 = 17.
7. How many more do you need to add to 15 to make 20?
5
Subtract 15 from 20: 20 − 15 = 5.
8. How many more do you need to add to 24 to make 50?
26
Subtract 24 from 50: 50 − 24 = 26.
9. How many more do you need to add to 30 to make 100?
70
Subtract 30 from 100: 100 − 30 = 70.
10. How many more do you need to add to 9 to make 20?
11
Subtract 9 from 20: 20 − 9 = 11.
11. How many more do you need to add to 96 to make 100?
4
Subtract 96 from 100: 100 − 96 = 4.
12. How many more do you need to add to 12 to make 20?
8
Subtract 12 from 20: 20 − 12 = 8.

12 questions · Seed 104776 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

1. How many more do you need to add to 11 to make 100?
11 · 100 · Complements to 10, 20 & 100
2. How many more do you need to add to 11 to make 30?
11 · 30 · Complements to 10, 20 & 100
3. How many more do you need to add to 33 to make 50?
33 · 50 · Complements to 10, 20 & 100
4. How many more do you need to add to 11 to make 50?
11 · 50 · Complements to 10, 20 & 100
5. How many more do you need to add to 9 to make 30?
9 · 30 · Complements to 10, 20 & 100
6. How many more do you need to add to 13 to make 30?
13 · 30 · Complements to 10, 20 & 100
7. How many more do you need to add to 15 to make 20?
15 · 20 · Complements to 10, 20 & 100
8. How many more do you need to add to 24 to make 50?
24 · 50 · Complements to 10, 20 & 100
9. How many more do you need to add to 30 to make 100?
30 · 100 · Complements to 10, 20 & 100
10. How many more do you need to add to 9 to make 20?
9 · 20 · Complements to 10, 20 & 100
11. How many more do you need to add to 96 to make 100?
96 · 100 · Complements to 10, 20 & 100
12. How many more do you need to add to 12 to make 20?
12 · 20 · Complements to 10, 20 & 100

12 questions · Seed 104776 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 7-9

Answers and reasoning. Review before teaching.

1. How many more do you need to add to 11 to make 100?
89
Subtract 11 from 100: 100 − 11 = 89.
2. How many more do you need to add to 11 to make 30?
19
Subtract 11 from 30: 30 − 11 = 19.
3. How many more do you need to add to 33 to make 50?
17
Subtract 33 from 50: 50 − 33 = 17.
4. How many more do you need to add to 11 to make 50?
39
Subtract 11 from 50: 50 − 11 = 39.
5. How many more do you need to add to 9 to make 30?
21
Subtract 9 from 30: 30 − 9 = 21.
6. How many more do you need to add to 13 to make 30?
17
Subtract 13 from 30: 30 − 13 = 17.
7. How many more do you need to add to 15 to make 20?
5
Subtract 15 from 20: 20 − 15 = 5.
8. How many more do you need to add to 24 to make 50?
26
Subtract 24 from 50: 50 − 24 = 26.
9. How many more do you need to add to 30 to make 100?
70
Subtract 30 from 100: 100 − 30 = 70.
10. How many more do you need to add to 9 to make 20?
11
Subtract 9 from 20: 20 − 9 = 11.
11. How many more do you need to add to 96 to make 100?
4
Subtract 96 from 100: 100 − 96 = 4.
12. How many more do you need to add to 12 to make 20?
8
Subtract 12 from 20: 20 − 12 = 8.

12 questions · Seed 104776 · Age guidance, not curriculum certification