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 71 · 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: 13, 16, ____, 22, 25.
19
The sequence increases by 3 each step: 16 + 3 = 19.
2. Find the missing number in the sequence: 9, 13, ____, 21, 25.
17
The sequence increases by 4 each step: 13 + 4 = 17.
3. Find the missing number in the sequence: 17, 23, ____, 35, 41.
29
The sequence increases by 6 each step: 23 + 6 = 29.
4. Find the missing number in the sequence: 2, 8, ____, 20, 26.
14
The sequence increases by 6 each step: 8 + 6 = 14.
5. Find the missing number in the sequence: 9, 17, ____, 33, 41.
25
The sequence increases by 8 each step: 17 + 8 = 25.
6. Find the missing number in the sequence: 13, 17, ____, 25, 29.
21
The sequence increases by 4 each step: 17 + 4 = 21.
7. Find the missing number in the sequence: 6, 9, ____, 15, 18.
12
The sequence increases by 3 each step: 9 + 3 = 12.
8. Find the missing number in the sequence: 9, 12, ____, 18, 21.
15
The sequence increases by 3 each step: 12 + 3 = 15.
9. Find the missing number in the sequence: 18, 24, ____, 36, 42.
30
The sequence increases by 6 each step: 24 + 6 = 30.
10. Find the missing number in the sequence: 3, 9, ____, 21, 27.
15
The sequence increases by 6 each step: 9 + 6 = 15.
11. Find the missing number in the sequence: 4, 13, ____, 31, 40.
22
The sequence increases by 9 each step: 13 + 9 = 22.
12. Find the missing number in the sequence: 6, 14, ____, 30, 38.
22
The sequence increases by 8 each step: 14 + 8 = 22.

12 questions · Seed 71 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 71 · 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: 13, 16, ____, 22, 25.
19
The sequence increases by 3 each step: 16 + 3 = 19.
2. Find the missing number in the sequence: 9, 13, ____, 21, 25.
17
The sequence increases by 4 each step: 13 + 4 = 17.
3. Find the missing number in the sequence: 17, 23, ____, 35, 41.
29
The sequence increases by 6 each step: 23 + 6 = 29.
4. Find the missing number in the sequence: 2, 8, ____, 20, 26.
14
The sequence increases by 6 each step: 8 + 6 = 14.
5. Find the missing number in the sequence: 9, 17, ____, 33, 41.
25
The sequence increases by 8 each step: 17 + 8 = 25.
6. Find the missing number in the sequence: 13, 17, ____, 25, 29.
21
The sequence increases by 4 each step: 17 + 4 = 21.
7. Find the missing number in the sequence: 6, 9, ____, 15, 18.
12
The sequence increases by 3 each step: 9 + 3 = 12.
8. Find the missing number in the sequence: 9, 12, ____, 18, 21.
15
The sequence increases by 3 each step: 12 + 3 = 15.
9. Find the missing number in the sequence: 18, 24, ____, 36, 42.
30
The sequence increases by 6 each step: 24 + 6 = 30.
10. Find the missing number in the sequence: 3, 9, ____, 21, 27.
15
The sequence increases by 6 each step: 9 + 6 = 15.
11. Find the missing number in the sequence: 4, 13, ____, 31, 40.
22
The sequence increases by 9 each step: 13 + 9 = 22.
12. Find the missing number in the sequence: 6, 14, ____, 30, 38.
22
The sequence increases by 8 each step: 14 + 8 = 22.

12 questions · Seed 71 · Age guidance, not curriculum certification