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 104742 · 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: 8, 18, ____, 38, 48.
28
The sequence increases by 10 each step: 18 + 10 = 28.
2. Find the missing number in the sequence: 17, 24, ____, 38, 45.
31
The sequence increases by 7 each step: 24 + 7 = 31.
3. Find the missing number in the sequence: 3, 7, ____, 15, 19.
11
The sequence increases by 4 each step: 7 + 4 = 11.
4. Find the missing number in the sequence: 18, 25, ____, 39, 46.
32
The sequence increases by 7 each step: 25 + 7 = 32.
5. Find the missing number in the sequence: 10, 16, ____, 28, 34.
22
The sequence increases by 6 each step: 16 + 6 = 22.
6. Find the missing number in the sequence: 13, 21, ____, 37, 45.
29
The sequence increases by 8 each step: 21 + 8 = 29.
7. Find the missing number in the sequence: 13, 19, ____, 31, 37.
25
The sequence increases by 6 each step: 19 + 6 = 25.
8. Find the missing number in the sequence: 12, 15, ____, 21, 24.
18
The sequence increases by 3 each step: 15 + 3 = 18.
9. Find the missing number in the sequence: 16, 24, ____, 40, 48.
32
The sequence increases by 8 each step: 24 + 8 = 32.
10. Find the missing number in the sequence: 19, 29, ____, 49, 59.
39
The sequence increases by 10 each step: 29 + 10 = 39.
11. Find the missing number in the sequence: 1, 8, ____, 22, 29.
15
The sequence increases by 7 each step: 8 + 7 = 15.
12. Find the missing number in the sequence: 18, 24, ____, 36, 42.
30
The sequence increases by 6 each step: 24 + 6 = 30.

12 questions · Seed 104742 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 7-9

Take your time. Show your thinking.

12 questions · Seed 104742 · 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: 8, 18, ____, 38, 48.
28
The sequence increases by 10 each step: 18 + 10 = 28.
2. Find the missing number in the sequence: 17, 24, ____, 38, 45.
31
The sequence increases by 7 each step: 24 + 7 = 31.
3. Find the missing number in the sequence: 3, 7, ____, 15, 19.
11
The sequence increases by 4 each step: 7 + 4 = 11.
4. Find the missing number in the sequence: 18, 25, ____, 39, 46.
32
The sequence increases by 7 each step: 25 + 7 = 32.
5. Find the missing number in the sequence: 10, 16, ____, 28, 34.
22
The sequence increases by 6 each step: 16 + 6 = 22.
6. Find the missing number in the sequence: 13, 21, ____, 37, 45.
29
The sequence increases by 8 each step: 21 + 8 = 29.
7. Find the missing number in the sequence: 13, 19, ____, 31, 37.
25
The sequence increases by 6 each step: 19 + 6 = 25.
8. Find the missing number in the sequence: 12, 15, ____, 21, 24.
18
The sequence increases by 3 each step: 15 + 3 = 18.
9. Find the missing number in the sequence: 16, 24, ____, 40, 48.
32
The sequence increases by 8 each step: 24 + 8 = 32.
10. Find the missing number in the sequence: 19, 29, ____, 49, 59.
39
The sequence increases by 10 each step: 29 + 10 = 39.
11. Find the missing number in the sequence: 1, 8, ____, 22, 29.
15
The sequence increases by 7 each step: 8 + 7 = 15.
12. Find the missing number in the sequence: 18, 24, ____, 36, 42.
30
The sequence increases by 6 each step: 24 + 6 = 30.

12 questions · Seed 104742 · Age guidance, not curriculum certification