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.

Choose “Save as PDF” to keep a copy. Use your browser’s paper setting for A4 or Letter.

Worksheet StudioPractice pack · Ages 4-6

Take your time. Show your thinking.

12 questions · Seed 100 · 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: 10, 12, ____, 16, 18.
14
The sequence increases by 2 each step: 12 + 2 = 14.
2. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
3. Find the missing number in the sequence: 6, 8, ____, 12, 14.
10
The sequence increases by 2 each step: 8 + 2 = 10.
4. Find the missing number in the sequence: 16, 21, ____, 31, 36.
26
The sequence increases by 5 each step: 21 + 5 = 26.
5. Find the missing number in the sequence: 18, 20, ____, 24, 26.
22
The sequence increases by 2 each step: 20 + 2 = 22.
6. Find the missing number in the sequence: 8, 9, ____, 11, 12.
10
The sequence increases by 1 each step: 9 + 1 = 10.
7. Find the missing number in the sequence: 13, 14, ____, 16, 17.
15
The sequence increases by 1 each step: 14 + 1 = 15.
8. Find the missing number in the sequence: 10, 15, ____, 25, 30.
20
The sequence increases by 5 each step: 15 + 5 = 20.
9. Find the missing number in the sequence: 14, 19, ____, 29, 34.
24
The sequence increases by 5 each step: 19 + 5 = 24.
10. Find the missing number in the sequence: 16, 17, ____, 19, 20.
18
The sequence increases by 1 each step: 17 + 1 = 18.
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: 9, 14, ____, 24, 29.
19
The sequence increases by 5 each step: 14 + 5 = 19.

12 questions · Seed 100 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 4-6

Take your time. Show your thinking.

12 questions · Seed 100 · 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: 10, 12, ____, 16, 18.
14
The sequence increases by 2 each step: 12 + 2 = 14.
2. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
3. Find the missing number in the sequence: 6, 8, ____, 12, 14.
10
The sequence increases by 2 each step: 8 + 2 = 10.
4. Find the missing number in the sequence: 16, 21, ____, 31, 36.
26
The sequence increases by 5 each step: 21 + 5 = 26.
5. Find the missing number in the sequence: 18, 20, ____, 24, 26.
22
The sequence increases by 2 each step: 20 + 2 = 22.
6. Find the missing number in the sequence: 8, 9, ____, 11, 12.
10
The sequence increases by 1 each step: 9 + 1 = 10.
7. Find the missing number in the sequence: 13, 14, ____, 16, 17.
15
The sequence increases by 1 each step: 14 + 1 = 15.
8. Find the missing number in the sequence: 10, 15, ____, 25, 30.
20
The sequence increases by 5 each step: 15 + 5 = 20.
9. Find the missing number in the sequence: 14, 19, ____, 29, 34.
24
The sequence increases by 5 each step: 19 + 5 = 24.
10. Find the missing number in the sequence: 16, 17, ____, 19, 20.
18
The sequence increases by 1 each step: 17 + 1 = 18.
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: 9, 14, ____, 24, 29.
19
The sequence increases by 5 each step: 14 + 5 = 19.

12 questions · Seed 100 · Age guidance, not curriculum certification