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 107 · 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: 14, 17, ____, 23, 26.
20
The sequence increases by 3 each step: 17 + 3 = 20.
2. Find the missing number in the sequence: 14, 22, ____, 38, 46.
30
The sequence increases by 8 each step: 22 + 8 = 30.
3. Find the missing number in the sequence: 4, 7, ____, 13, 16.
10
The sequence increases by 3 each step: 7 + 3 = 10.
4. Find the missing number in the sequence: 18, 27, ____, 45, 54.
36
The sequence increases by 9 each step: 27 + 9 = 36.
5. Find the missing number in the sequence: 2, 5, ____, 11, 14.
8
The sequence increases by 3 each step: 5 + 3 = 8.
6. Find the missing number in the sequence: 8, 16, ____, 32, 40.
24
The sequence increases by 8 each step: 16 + 8 = 24.
7. Find the missing number in the sequence: 12, 16, ____, 24, 28.
20
The sequence increases by 4 each step: 16 + 4 = 20.
8. Find the missing number in the sequence: 20, 27, ____, 41, 48.
34
The sequence increases by 7 each step: 27 + 7 = 34.
9. Find the missing number in the sequence: 14, 18, ____, 26, 30.
22
The sequence increases by 4 each step: 18 + 4 = 22.
10. Find the missing number in the sequence: 10, 13, ____, 19, 22.
16
The sequence increases by 3 each step: 13 + 3 = 16.
11. Find the missing number in the sequence: 9, 15, ____, 27, 33.
21
The sequence increases by 6 each step: 15 + 6 = 21.
12. Find the missing number in the sequence: 6, 10, ____, 18, 22.
14
The sequence increases by 4 each step: 10 + 4 = 14.

12 questions · Seed 107 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 107 · 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: 14, 17, ____, 23, 26.
20
The sequence increases by 3 each step: 17 + 3 = 20.
2. Find the missing number in the sequence: 14, 22, ____, 38, 46.
30
The sequence increases by 8 each step: 22 + 8 = 30.
3. Find the missing number in the sequence: 4, 7, ____, 13, 16.
10
The sequence increases by 3 each step: 7 + 3 = 10.
4. Find the missing number in the sequence: 18, 27, ____, 45, 54.
36
The sequence increases by 9 each step: 27 + 9 = 36.
5. Find the missing number in the sequence: 2, 5, ____, 11, 14.
8
The sequence increases by 3 each step: 5 + 3 = 8.
6. Find the missing number in the sequence: 8, 16, ____, 32, 40.
24
The sequence increases by 8 each step: 16 + 8 = 24.
7. Find the missing number in the sequence: 12, 16, ____, 24, 28.
20
The sequence increases by 4 each step: 16 + 4 = 20.
8. Find the missing number in the sequence: 20, 27, ____, 41, 48.
34
The sequence increases by 7 each step: 27 + 7 = 34.
9. Find the missing number in the sequence: 14, 18, ____, 26, 30.
22
The sequence increases by 4 each step: 18 + 4 = 22.
10. Find the missing number in the sequence: 10, 13, ____, 19, 22.
16
The sequence increases by 3 each step: 13 + 3 = 16.
11. Find the missing number in the sequence: 9, 15, ____, 27, 33.
21
The sequence increases by 6 each step: 15 + 6 = 21.
12. Find the missing number in the sequence: 6, 10, ____, 18, 22.
14
The sequence increases by 4 each step: 10 + 4 = 14.

12 questions · Seed 107 · Age guidance, not curriculum certification