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 99 · 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: 11, 13, ____, 17, 19.
15
The sequence increases by 2 each step: 13 + 2 = 15.
2. Find the missing number in the sequence: 12, 17, ____, 27, 32.
22
The sequence increases by 5 each step: 17 + 5 = 22.
3. Find the missing number in the sequence: 8, 10, ____, 14, 16.
12
The sequence increases by 2 each step: 10 + 2 = 12.
4. Find the missing number in the sequence: 17, 18, ____, 20, 21.
19
The sequence increases by 1 each step: 18 + 1 = 19.
5. Find the missing number in the sequence: 2, 7, ____, 17, 22.
12
The sequence increases by 5 each step: 7 + 5 = 12.
6. Find the missing number in the sequence: 16, 18, ____, 22, 24.
20
The sequence increases by 2 each step: 18 + 2 = 20.
7. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15
The sequence increases by 5 each step: 10 + 5 = 15.
8. Find the missing number in the sequence: 12, 14, ____, 18, 20.
16
The sequence increases by 2 each step: 14 + 2 = 16.
9. Find the missing number in the sequence: 13, 18, ____, 28, 33.
23
The sequence increases by 5 each step: 18 + 5 = 23.
10. Find the missing number in the sequence: 11, 16, ____, 26, 31.
21
The sequence increases by 5 each step: 16 + 5 = 21.
11. Find the missing number in the sequence: 18, 19, ____, 21, 22.
20
The sequence increases by 1 each step: 19 + 1 = 20.
12. Find the missing number in the sequence: 11, 12, ____, 14, 15.
13
The sequence increases by 1 each step: 12 + 1 = 13.

12 questions · Seed 99 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 4-6

Take your time. Show your thinking.

12 questions · Seed 99 · 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: 11, 13, ____, 17, 19.
15
The sequence increases by 2 each step: 13 + 2 = 15.
2. Find the missing number in the sequence: 12, 17, ____, 27, 32.
22
The sequence increases by 5 each step: 17 + 5 = 22.
3. Find the missing number in the sequence: 8, 10, ____, 14, 16.
12
The sequence increases by 2 each step: 10 + 2 = 12.
4. Find the missing number in the sequence: 17, 18, ____, 20, 21.
19
The sequence increases by 1 each step: 18 + 1 = 19.
5. Find the missing number in the sequence: 2, 7, ____, 17, 22.
12
The sequence increases by 5 each step: 7 + 5 = 12.
6. Find the missing number in the sequence: 16, 18, ____, 22, 24.
20
The sequence increases by 2 each step: 18 + 2 = 20.
7. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15
The sequence increases by 5 each step: 10 + 5 = 15.
8. Find the missing number in the sequence: 12, 14, ____, 18, 20.
16
The sequence increases by 2 each step: 14 + 2 = 16.
9. Find the missing number in the sequence: 13, 18, ____, 28, 33.
23
The sequence increases by 5 each step: 18 + 5 = 23.
10. Find the missing number in the sequence: 11, 16, ____, 26, 31.
21
The sequence increases by 5 each step: 16 + 5 = 21.
11. Find the missing number in the sequence: 18, 19, ____, 21, 22.
20
The sequence increases by 1 each step: 19 + 1 = 20.
12. Find the missing number in the sequence: 11, 12, ____, 14, 15.
13
The sequence increases by 1 each step: 12 + 1 = 13.

12 questions · Seed 99 · Age guidance, not curriculum certification