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 42 · 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: 15, 20, ____, 30, 35.
25
The sequence increases by 5 each step: 20 + 5 = 25.
2. Find the missing number in the sequence: 11, 16, ____, 26, 31.
21
The sequence increases by 5 each step: 16 + 5 = 21.
3. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
4. Find the missing number in the sequence: 3, 8, ____, 18, 23.
13
The sequence increases by 5 each step: 8 + 5 = 13.
5. Find the missing number in the sequence: 11, 13, ____, 17, 19.
15
The sequence increases by 2 each step: 13 + 2 = 15.
6. Find the missing number in the sequence: 6, 8, ____, 12, 14.
10
The sequence increases by 2 each step: 8 + 2 = 10.
7. Find the missing number in the sequence: 2, 3, ____, 5, 6.
4
The sequence increases by 1 each step: 3 + 1 = 4.
8. Find the missing number in the sequence: 5, 6, ____, 8, 9.
7
The sequence increases by 1 each step: 6 + 1 = 7.
9. Find the missing number in the sequence: 14, 15, ____, 17, 18.
16
The sequence increases by 1 each step: 15 + 1 = 16.
10. Find the missing number in the sequence: 12, 13, ____, 15, 16.
14
The sequence increases by 1 each step: 13 + 1 = 14.
11. Find the missing number in the sequence: 4, 5, ____, 7, 8.
6
The sequence increases by 1 each step: 5 + 1 = 6.
12. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15
The sequence increases by 5 each step: 10 + 5 = 15.

12 questions · Seed 42 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 4-6

Take your time. Show your thinking.

12 questions · Seed 42 · 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: 15, 20, ____, 30, 35.
25
The sequence increases by 5 each step: 20 + 5 = 25.
2. Find the missing number in the sequence: 11, 16, ____, 26, 31.
21
The sequence increases by 5 each step: 16 + 5 = 21.
3. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
4. Find the missing number in the sequence: 3, 8, ____, 18, 23.
13
The sequence increases by 5 each step: 8 + 5 = 13.
5. Find the missing number in the sequence: 11, 13, ____, 17, 19.
15
The sequence increases by 2 each step: 13 + 2 = 15.
6. Find the missing number in the sequence: 6, 8, ____, 12, 14.
10
The sequence increases by 2 each step: 8 + 2 = 10.
7. Find the missing number in the sequence: 2, 3, ____, 5, 6.
4
The sequence increases by 1 each step: 3 + 1 = 4.
8. Find the missing number in the sequence: 5, 6, ____, 8, 9.
7
The sequence increases by 1 each step: 6 + 1 = 7.
9. Find the missing number in the sequence: 14, 15, ____, 17, 18.
16
The sequence increases by 1 each step: 15 + 1 = 16.
10. Find the missing number in the sequence: 12, 13, ____, 15, 16.
14
The sequence increases by 1 each step: 13 + 1 = 14.
11. Find the missing number in the sequence: 4, 5, ____, 7, 8.
6
The sequence increases by 1 each step: 5 + 1 = 6.
12. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15
The sequence increases by 5 each step: 10 + 5 = 15.

12 questions · Seed 42 · Age guidance, not curriculum certification