Back to worksheetsReasoningAges 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.
Worksheet StudioPractice pack · Ages 4-6
Missing sequence terms
Take your time. Show your thinking.
1. Find the missing number in the sequence: 16, 21, ____, 31, 36.
2. Find the missing number in the sequence: 20, 25, ____, 35, 40.
3. Find the missing number in the sequence: 5, 6, ____, 8, 9.
4. Find the missing number in the sequence: 7, 8, ____, 10, 11.
5. Find the missing number in the sequence: 7, 9, ____, 13, 15.
6. Find the missing number in the sequence: 14, 15, ____, 17, 18.
7. Find the missing number in the sequence: 20, 22, ____, 26, 28.
8. Find the missing number in the sequence: 5, 10, ____, 20, 25.
9. Find the missing number in the sequence: 4, 6, ____, 10, 12.
10. Find the missing number in the sequence: 18, 19, ____, 21, 22.
11. Find the missing number in the sequence: 18, 23, ____, 33, 38.
12. Find the missing number in the sequence: 12, 13, ____, 15, 16.
12 questions · Seed 58 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 4-6
Missing sequence terms
Answers and reasoning. Review before teaching.
1. Find the missing number in the sequence: 16, 21, ____, 31, 36.
26The sequence increases by 5 each step: 21 + 5 = 26.
2. Find the missing number in the sequence: 20, 25, ____, 35, 40.
30The sequence increases by 5 each step: 25 + 5 = 30.
3. Find the missing number in the sequence: 5, 6, ____, 8, 9.
7The sequence increases by 1 each step: 6 + 1 = 7.
4. Find the missing number in the sequence: 7, 8, ____, 10, 11.
9The sequence increases by 1 each step: 8 + 1 = 9.
5. Find the missing number in the sequence: 7, 9, ____, 13, 15.
11The sequence increases by 2 each step: 9 + 2 = 11.
6. Find the missing number in the sequence: 14, 15, ____, 17, 18.
16The sequence increases by 1 each step: 15 + 1 = 16.
7. Find the missing number in the sequence: 20, 22, ____, 26, 28.
24The sequence increases by 2 each step: 22 + 2 = 24.
8. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15The sequence increases by 5 each step: 10 + 5 = 15.
9. Find the missing number in the sequence: 4, 6, ____, 10, 12.
8The sequence increases by 2 each step: 6 + 2 = 8.
10. Find the missing number in the sequence: 18, 19, ____, 21, 22.
20The sequence increases by 1 each step: 19 + 1 = 20.
11. Find the missing number in the sequence: 18, 23, ____, 33, 38.
28The sequence increases by 5 each step: 23 + 5 = 28.
12. Find the missing number in the sequence: 12, 13, ____, 15, 16.
14The sequence increases by 1 each step: 13 + 1 = 14.
12 questions · Seed 58 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 4-6
Missing sequence terms
Take your time. Show your thinking.
1. Find the missing number in the sequence: 16, 21, ____, 31, 36.
2. Find the missing number in the sequence: 20, 25, ____, 35, 40.
3. Find the missing number in the sequence: 5, 6, ____, 8, 9.
4. Find the missing number in the sequence: 7, 8, ____, 10, 11.
5. Find the missing number in the sequence: 7, 9, ____, 13, 15.
6. Find the missing number in the sequence: 14, 15, ____, 17, 18.
7. Find the missing number in the sequence: 20, 22, ____, 26, 28.
8. Find the missing number in the sequence: 5, 10, ____, 20, 25.
9. Find the missing number in the sequence: 4, 6, ____, 10, 12.
10. Find the missing number in the sequence: 18, 19, ____, 21, 22.
11. Find the missing number in the sequence: 18, 23, ____, 33, 38.
12. Find the missing number in the sequence: 12, 13, ____, 15, 16.
12 questions · Seed 58 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 4-6
Missing sequence terms
Answers and reasoning. Review before teaching.
1. Find the missing number in the sequence: 16, 21, ____, 31, 36.
26The sequence increases by 5 each step: 21 + 5 = 26.
2. Find the missing number in the sequence: 20, 25, ____, 35, 40.
30The sequence increases by 5 each step: 25 + 5 = 30.
3. Find the missing number in the sequence: 5, 6, ____, 8, 9.
7The sequence increases by 1 each step: 6 + 1 = 7.
4. Find the missing number in the sequence: 7, 8, ____, 10, 11.
9The sequence increases by 1 each step: 8 + 1 = 9.
5. Find the missing number in the sequence: 7, 9, ____, 13, 15.
11The sequence increases by 2 each step: 9 + 2 = 11.
6. Find the missing number in the sequence: 14, 15, ____, 17, 18.
16The sequence increases by 1 each step: 15 + 1 = 16.
7. Find the missing number in the sequence: 20, 22, ____, 26, 28.
24The sequence increases by 2 each step: 22 + 2 = 24.
8. Find the missing number in the sequence: 5, 10, ____, 20, 25.
15The sequence increases by 5 each step: 10 + 5 = 15.
9. Find the missing number in the sequence: 4, 6, ____, 10, 12.
8The sequence increases by 2 each step: 6 + 2 = 8.
10. Find the missing number in the sequence: 18, 19, ____, 21, 22.
20The sequence increases by 1 each step: 19 + 1 = 20.
11. Find the missing number in the sequence: 18, 23, ____, 33, 38.
28The sequence increases by 5 each step: 23 + 5 = 28.
12. Find the missing number in the sequence: 12, 13, ____, 15, 16.
14The sequence increases by 1 each step: 13 + 1 = 14.
12 questions · Seed 58 · Age guidance, not curriculum certification