ReasoningAges 4-6

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 4-6

Take your time. Show your thinking.

12 questions · Seed 88 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 4-6

Answers and reasoning. Review before teaching.

1. Find the missing number in the sequence: 16, 21, ____, 31, 36.
26
The sequence increases by 5 each step: 21 + 5 = 26.
2. Find the missing number in the sequence: 18, 19, ____, 21, 22.
20
The sequence increases by 1 each step: 19 + 1 = 20.
3. Find the missing number in the sequence: 19, 21, ____, 25, 27.
23
The sequence increases by 2 each step: 21 + 2 = 23.
4. Find the missing number in the sequence: 4, 5, ____, 7, 8.
6
The sequence increases by 1 each step: 5 + 1 = 6.
5. Find the missing number in the sequence: 12, 14, ____, 18, 20.
16
The sequence increases by 2 each step: 14 + 2 = 16.
6. Find the missing number in the sequence: 13, 15, ____, 19, 21.
17
The sequence increases by 2 each step: 15 + 2 = 17.
7. Find the missing number in the sequence: 12, 13, ____, 15, 16.
14
The sequence increases by 1 each step: 13 + 1 = 14.
8. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
9. Find the missing number in the sequence: 20, 21, ____, 23, 24.
22
The sequence increases by 1 each step: 21 + 1 = 22.
10. Find the missing number in the sequence: 9, 11, ____, 15, 17.
13
The sequence increases by 2 each step: 11 + 2 = 13.
11. Find the missing number in the sequence: 1, 3, ____, 7, 9.
5
The sequence increases by 2 each step: 3 + 2 = 5.
12. Find the missing number in the sequence: 15, 17, ____, 21, 23.
19
The sequence increases by 2 each step: 17 + 2 = 19.

12 questions · Seed 88 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 4-6

Take your time. Show your thinking.

12 questions · Seed 88 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 4-6

Answers and reasoning. Review before teaching.

1. Find the missing number in the sequence: 16, 21, ____, 31, 36.
26
The sequence increases by 5 each step: 21 + 5 = 26.
2. Find the missing number in the sequence: 18, 19, ____, 21, 22.
20
The sequence increases by 1 each step: 19 + 1 = 20.
3. Find the missing number in the sequence: 19, 21, ____, 25, 27.
23
The sequence increases by 2 each step: 21 + 2 = 23.
4. Find the missing number in the sequence: 4, 5, ____, 7, 8.
6
The sequence increases by 1 each step: 5 + 1 = 6.
5. Find the missing number in the sequence: 12, 14, ____, 18, 20.
16
The sequence increases by 2 each step: 14 + 2 = 16.
6. Find the missing number in the sequence: 13, 15, ____, 19, 21.
17
The sequence increases by 2 each step: 15 + 2 = 17.
7. Find the missing number in the sequence: 12, 13, ____, 15, 16.
14
The sequence increases by 1 each step: 13 + 1 = 14.
8. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
9. Find the missing number in the sequence: 20, 21, ____, 23, 24.
22
The sequence increases by 1 each step: 21 + 1 = 22.
10. Find the missing number in the sequence: 9, 11, ____, 15, 17.
13
The sequence increases by 2 each step: 11 + 2 = 13.
11. Find the missing number in the sequence: 1, 3, ____, 7, 9.
5
The sequence increases by 2 each step: 3 + 2 = 5.
12. Find the missing number in the sequence: 15, 17, ____, 21, 23.
19
The sequence increases by 2 each step: 17 + 2 = 19.

12 questions · Seed 88 · Age guidance, not curriculum certification