ReasoningAges 7-9

Missing sequence terms

Use the constant step size between terms to find the missing middle number in a sequence. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 59 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 7-9

Answers and reasoning. Review before teaching.

1. Find the missing number in the sequence: 1, 11, ____, 31, 41.
21
The sequence increases by 10 each step: 11 + 10 = 21.
2. Find the missing number in the sequence: 19, 23, ____, 31, 35.
27
The sequence increases by 4 each step: 23 + 4 = 27.
3. Find the missing number in the sequence: 10, 16, ____, 28, 34.
22
The sequence increases by 6 each step: 16 + 6 = 22.
4. Find the missing number in the sequence: 14, 22, ____, 38, 46.
30
The sequence increases by 8 each step: 22 + 8 = 30.
5. Find the missing number in the sequence: 13, 22, ____, 40, 49.
31
The sequence increases by 9 each step: 22 + 9 = 31.
6. Find the missing number in the sequence: 6, 13, ____, 27, 34.
20
The sequence increases by 7 each step: 13 + 7 = 20.
7. Find the missing number in the sequence: 4, 13, ____, 31, 40.
22
The sequence increases by 9 each step: 13 + 9 = 22.
8. Find the missing number in the sequence: 18, 25, ____, 39, 46.
32
The sequence increases by 7 each step: 25 + 7 = 32.
9. Find the missing number in the sequence: 6, 16, ____, 36, 46.
26
The sequence increases by 10 each step: 16 + 10 = 26.
10. Find the missing number in the sequence: 6, 12, ____, 24, 30.
18
The sequence increases by 6 each step: 12 + 6 = 18.
11. Find the missing number in the sequence: 4, 14, ____, 34, 44.
24
The sequence increases by 10 each step: 14 + 10 = 24.
12. Find the missing number in the sequence: 15, 23, ____, 39, 47.
31
The sequence increases by 8 each step: 23 + 8 = 31.

12 questions · Seed 59 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 59 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 7-9

Answers and reasoning. Review before teaching.

1. Find the missing number in the sequence: 1, 11, ____, 31, 41.
21
The sequence increases by 10 each step: 11 + 10 = 21.
2. Find the missing number in the sequence: 19, 23, ____, 31, 35.
27
The sequence increases by 4 each step: 23 + 4 = 27.
3. Find the missing number in the sequence: 10, 16, ____, 28, 34.
22
The sequence increases by 6 each step: 16 + 6 = 22.
4. Find the missing number in the sequence: 14, 22, ____, 38, 46.
30
The sequence increases by 8 each step: 22 + 8 = 30.
5. Find the missing number in the sequence: 13, 22, ____, 40, 49.
31
The sequence increases by 9 each step: 22 + 9 = 31.
6. Find the missing number in the sequence: 6, 13, ____, 27, 34.
20
The sequence increases by 7 each step: 13 + 7 = 20.
7. Find the missing number in the sequence: 4, 13, ____, 31, 40.
22
The sequence increases by 9 each step: 13 + 9 = 22.
8. Find the missing number in the sequence: 18, 25, ____, 39, 46.
32
The sequence increases by 7 each step: 25 + 7 = 32.
9. Find the missing number in the sequence: 6, 16, ____, 36, 46.
26
The sequence increases by 10 each step: 16 + 10 = 26.
10. Find the missing number in the sequence: 6, 12, ____, 24, 30.
18
The sequence increases by 6 each step: 12 + 6 = 18.
11. Find the missing number in the sequence: 4, 14, ____, 34, 44.
24
The sequence increases by 10 each step: 14 + 10 = 24.
12. Find the missing number in the sequence: 15, 23, ____, 39, 47.
31
The sequence increases by 8 each step: 23 + 8 = 31.

12 questions · Seed 59 · Age guidance, not curriculum certification