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 104757 · 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: 17, 20, ____, 26, 29.
23
The sequence increases by 3 each step: 20 + 3 = 23.
2. Find the missing number in the sequence: 11, 14, ____, 20, 23.
17
The sequence increases by 3 each step: 14 + 3 = 17.
3. Find the missing number in the sequence: 14, 20, ____, 32, 38.
26
The sequence increases by 6 each step: 20 + 6 = 26.
4. Find the missing number in the sequence: 13, 20, ____, 34, 41.
27
The sequence increases by 7 each step: 20 + 7 = 27.
5. Find the missing number in the sequence: 16, 24, ____, 40, 48.
32
The sequence increases by 8 each step: 24 + 8 = 32.
6. Find the missing number in the sequence: 6, 14, ____, 30, 38.
22
The sequence increases by 8 each step: 14 + 8 = 22.
7. Find the missing number in the sequence: 18, 21, ____, 27, 30.
24
The sequence increases by 3 each step: 21 + 3 = 24.
8. Find the missing number in the sequence: 20, 23, ____, 29, 32.
26
The sequence increases by 3 each step: 23 + 3 = 26.
9. Find the missing number in the sequence: 2, 11, ____, 29, 38.
20
The sequence increases by 9 each step: 11 + 9 = 20.
10. Find the missing number in the sequence: 20, 26, ____, 38, 44.
32
The sequence increases by 6 each step: 26 + 6 = 32.
11. Find the missing number in the sequence: 8, 18, ____, 38, 48.
28
The sequence increases by 10 each step: 18 + 10 = 28.
12. Find the missing number in the sequence: 3, 12, ____, 30, 39.
21
The sequence increases by 9 each step: 12 + 9 = 21.

12 questions · Seed 104757 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 104757 · 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: 17, 20, ____, 26, 29.
23
The sequence increases by 3 each step: 20 + 3 = 23.
2. Find the missing number in the sequence: 11, 14, ____, 20, 23.
17
The sequence increases by 3 each step: 14 + 3 = 17.
3. Find the missing number in the sequence: 14, 20, ____, 32, 38.
26
The sequence increases by 6 each step: 20 + 6 = 26.
4. Find the missing number in the sequence: 13, 20, ____, 34, 41.
27
The sequence increases by 7 each step: 20 + 7 = 27.
5. Find the missing number in the sequence: 16, 24, ____, 40, 48.
32
The sequence increases by 8 each step: 24 + 8 = 32.
6. Find the missing number in the sequence: 6, 14, ____, 30, 38.
22
The sequence increases by 8 each step: 14 + 8 = 22.
7. Find the missing number in the sequence: 18, 21, ____, 27, 30.
24
The sequence increases by 3 each step: 21 + 3 = 24.
8. Find the missing number in the sequence: 20, 23, ____, 29, 32.
26
The sequence increases by 3 each step: 23 + 3 = 26.
9. Find the missing number in the sequence: 2, 11, ____, 29, 38.
20
The sequence increases by 9 each step: 11 + 9 = 20.
10. Find the missing number in the sequence: 20, 26, ____, 38, 44.
32
The sequence increases by 6 each step: 26 + 6 = 32.
11. Find the missing number in the sequence: 8, 18, ____, 38, 48.
28
The sequence increases by 10 each step: 18 + 10 = 28.
12. Find the missing number in the sequence: 3, 12, ____, 30, 39.
21
The sequence increases by 9 each step: 12 + 9 = 21.

12 questions · Seed 104757 · Age guidance, not curriculum certification