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 73 · 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: 20, 21, ____, 23, 24.
22
The sequence increases by 1 each step: 21 + 1 = 22.
2. Find the missing number in the sequence: 9, 11, ____, 15, 17.
13
The sequence increases by 2 each step: 11 + 2 = 13.
3. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15
The sequence increases by 5 each step: 10 + 5 = 15.
4. Find the missing number in the sequence: 14, 15, ____, 17, 18.
16
The sequence increases by 1 each step: 15 + 1 = 16.
5. Find the missing number in the sequence: 3, 5, ____, 9, 11.
7
The sequence increases by 2 each step: 5 + 2 = 7.
6. Find the missing number in the sequence: 7, 9, ____, 13, 15.
11
The sequence increases by 2 each step: 9 + 2 = 11.
7. Find the missing number in the sequence: 7, 8, ____, 10, 11.
9
The sequence increases by 1 each step: 8 + 1 = 9.
8. Find the missing number in the sequence: 19, 21, ____, 25, 27.
23
The sequence increases by 2 each step: 21 + 2 = 23.
9. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
10. Find the missing number in the sequence: 14, 16, ____, 20, 22.
18
The sequence increases by 2 each step: 16 + 2 = 18.
11. Find the missing number in the sequence: 15, 16, ____, 18, 19.
17
The sequence increases by 1 each step: 16 + 1 = 17.
12. Find the missing number in the sequence: 20, 22, ____, 26, 28.
24
The sequence increases by 2 each step: 22 + 2 = 24.

12 questions · Seed 73 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 4-6

Take your time. Show your thinking.

12 questions · Seed 73 · 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: 20, 21, ____, 23, 24.
22
The sequence increases by 1 each step: 21 + 1 = 22.
2. Find the missing number in the sequence: 9, 11, ____, 15, 17.
13
The sequence increases by 2 each step: 11 + 2 = 13.
3. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15
The sequence increases by 5 each step: 10 + 5 = 15.
4. Find the missing number in the sequence: 14, 15, ____, 17, 18.
16
The sequence increases by 1 each step: 15 + 1 = 16.
5. Find the missing number in the sequence: 3, 5, ____, 9, 11.
7
The sequence increases by 2 each step: 5 + 2 = 7.
6. Find the missing number in the sequence: 7, 9, ____, 13, 15.
11
The sequence increases by 2 each step: 9 + 2 = 11.
7. Find the missing number in the sequence: 7, 8, ____, 10, 11.
9
The sequence increases by 1 each step: 8 + 1 = 9.
8. Find the missing number in the sequence: 19, 21, ____, 25, 27.
23
The sequence increases by 2 each step: 21 + 2 = 23.
9. Find the missing number in the sequence: 1, 2, ____, 4, 5.
3
The sequence increases by 1 each step: 2 + 1 = 3.
10. Find the missing number in the sequence: 14, 16, ____, 20, 22.
18
The sequence increases by 2 each step: 16 + 2 = 18.
11. Find the missing number in the sequence: 15, 16, ____, 18, 19.
17
The sequence increases by 1 each step: 16 + 1 = 17.
12. Find the missing number in the sequence: 20, 22, ____, 26, 28.
24
The sequence increases by 2 each step: 22 + 2 = 24.

12 questions · Seed 73 · Age guidance, not curriculum certification