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 91 · 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: 16, 25, ____, 43, 52.
34
The sequence increases by 9 each step: 25 + 9 = 34.
2. Find the missing number in the sequence: 18, 26, ____, 42, 50.
34
The sequence increases by 8 each step: 26 + 8 = 34.
3. Find the missing number in the sequence: 19, 29, ____, 49, 59.
39
The sequence increases by 10 each step: 29 + 10 = 39.
4. Find the missing number in the sequence: 16, 23, ____, 37, 44.
30
The sequence increases by 7 each step: 23 + 7 = 30.
5. Find the missing number in the sequence: 2, 9, ____, 23, 30.
16
The sequence increases by 7 each step: 9 + 7 = 16.
6. Find the missing number in the sequence: 14, 22, ____, 38, 46.
30
The sequence increases by 8 each step: 22 + 8 = 30.
7. Find the missing number in the sequence: 6, 13, ____, 27, 34.
20
The sequence increases by 7 each step: 13 + 7 = 20.
8. Find the missing number in the sequence: 4, 8, ____, 16, 20.
12
The sequence increases by 4 each step: 8 + 4 = 12.
9. Find the missing number in the sequence: 8, 12, ____, 20, 24.
16
The sequence increases by 4 each step: 12 + 4 = 16.
10. Find the missing number in the sequence: 13, 17, ____, 25, 29.
21
The sequence increases by 4 each step: 17 + 4 = 21.
11. Find the missing number in the sequence: 20, 28, ____, 44, 52.
36
The sequence increases by 8 each step: 28 + 8 = 36.
12. Find the missing number in the sequence: 19, 25, ____, 37, 43.
31
The sequence increases by 6 each step: 25 + 6 = 31.

12 questions · Seed 91 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 91 · 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: 16, 25, ____, 43, 52.
34
The sequence increases by 9 each step: 25 + 9 = 34.
2. Find the missing number in the sequence: 18, 26, ____, 42, 50.
34
The sequence increases by 8 each step: 26 + 8 = 34.
3. Find the missing number in the sequence: 19, 29, ____, 49, 59.
39
The sequence increases by 10 each step: 29 + 10 = 39.
4. Find the missing number in the sequence: 16, 23, ____, 37, 44.
30
The sequence increases by 7 each step: 23 + 7 = 30.
5. Find the missing number in the sequence: 2, 9, ____, 23, 30.
16
The sequence increases by 7 each step: 9 + 7 = 16.
6. Find the missing number in the sequence: 14, 22, ____, 38, 46.
30
The sequence increases by 8 each step: 22 + 8 = 30.
7. Find the missing number in the sequence: 6, 13, ____, 27, 34.
20
The sequence increases by 7 each step: 13 + 7 = 20.
8. Find the missing number in the sequence: 4, 8, ____, 16, 20.
12
The sequence increases by 4 each step: 8 + 4 = 12.
9. Find the missing number in the sequence: 8, 12, ____, 20, 24.
16
The sequence increases by 4 each step: 12 + 4 = 16.
10. Find the missing number in the sequence: 13, 17, ____, 25, 29.
21
The sequence increases by 4 each step: 17 + 4 = 21.
11. Find the missing number in the sequence: 20, 28, ____, 44, 52.
36
The sequence increases by 8 each step: 28 + 8 = 36.
12. Find the missing number in the sequence: 19, 25, ____, 37, 43.
31
The sequence increases by 6 each step: 25 + 6 = 31.

12 questions · Seed 91 · Age guidance, not curriculum certification