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 63 · 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: 9, 17, ____, 33, 41.
25
The sequence increases by 8 each step: 17 + 8 = 25.
2. Find the missing number in the sequence: 14, 23, ____, 41, 50.
32
The sequence increases by 9 each step: 23 + 9 = 32.
3. Find the missing number in the sequence: 13, 17, ____, 25, 29.
21
The sequence increases by 4 each step: 17 + 4 = 21.
4. Find the missing number in the sequence: 4, 12, ____, 28, 36.
20
The sequence increases by 8 each step: 12 + 8 = 20.
5. Find the missing number in the sequence: 1, 5, ____, 13, 17.
9
The sequence increases by 4 each step: 5 + 4 = 9.
6. Find the missing number in the sequence: 15, 18, ____, 24, 27.
21
The sequence increases by 3 each step: 18 + 3 = 21.
7. Find the missing number in the sequence: 13, 23, ____, 43, 53.
33
The sequence increases by 10 each step: 23 + 10 = 33.
8. Find the missing number in the sequence: 19, 26, ____, 40, 47.
33
The sequence increases by 7 each step: 26 + 7 = 33.
9. Find the missing number in the sequence: 18, 25, ____, 39, 46.
32
The sequence increases by 7 each step: 25 + 7 = 32.
10. Find the missing number in the sequence: 15, 24, ____, 42, 51.
33
The sequence increases by 9 each step: 24 + 9 = 33.
11. Find the missing number in the sequence: 17, 20, ____, 26, 29.
23
The sequence increases by 3 each step: 20 + 3 = 23.
12. Find the missing number in the sequence: 13, 22, ____, 40, 49.
31
The sequence increases by 9 each step: 22 + 9 = 31.

12 questions · Seed 63 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 63 · 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: 9, 17, ____, 33, 41.
25
The sequence increases by 8 each step: 17 + 8 = 25.
2. Find the missing number in the sequence: 14, 23, ____, 41, 50.
32
The sequence increases by 9 each step: 23 + 9 = 32.
3. Find the missing number in the sequence: 13, 17, ____, 25, 29.
21
The sequence increases by 4 each step: 17 + 4 = 21.
4. Find the missing number in the sequence: 4, 12, ____, 28, 36.
20
The sequence increases by 8 each step: 12 + 8 = 20.
5. Find the missing number in the sequence: 1, 5, ____, 13, 17.
9
The sequence increases by 4 each step: 5 + 4 = 9.
6. Find the missing number in the sequence: 15, 18, ____, 24, 27.
21
The sequence increases by 3 each step: 18 + 3 = 21.
7. Find the missing number in the sequence: 13, 23, ____, 43, 53.
33
The sequence increases by 10 each step: 23 + 10 = 33.
8. Find the missing number in the sequence: 19, 26, ____, 40, 47.
33
The sequence increases by 7 each step: 26 + 7 = 33.
9. Find the missing number in the sequence: 18, 25, ____, 39, 46.
32
The sequence increases by 7 each step: 25 + 7 = 32.
10. Find the missing number in the sequence: 15, 24, ____, 42, 51.
33
The sequence increases by 9 each step: 24 + 9 = 33.
11. Find the missing number in the sequence: 17, 20, ____, 26, 29.
23
The sequence increases by 3 each step: 20 + 3 = 23.
12. Find the missing number in the sequence: 13, 22, ____, 40, 49.
31
The sequence increases by 9 each step: 22 + 9 = 31.

12 questions · Seed 63 · Age guidance, not curriculum certification