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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: 18, 20, ____, 24, 26.
3. Find the missing number in the sequence: 19, 24, ____, 34, 39.
4. Find the missing number in the sequence: 16, 18, ____, 22, 24.
5. Find the missing number in the sequence: 2, 4, ____, 8, 10.
6. Find the missing number in the sequence: 14, 16, ____, 20, 22.
7. Find the missing number in the sequence: 6, 8, ____, 12, 14.
8. Find the missing number in the sequence: 4, 5, ____, 7, 8.
9. Find the missing number in the sequence: 8, 9, ____, 11, 12.
10. Find the missing number in the sequence: 13, 14, ____, 16, 17.
11. Find the missing number in the sequence: 20, 25, ____, 35, 40.
12. Find the missing number in the sequence: 19, 20, ____, 22, 23.
12 questions · Seed 91 · 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: 18, 20, ____, 24, 26.
22The sequence increases by 2 each step: 20 + 2 = 22.
3. Find the missing number in the sequence: 19, 24, ____, 34, 39.
29The sequence increases by 5 each step: 24 + 5 = 29.
4. Find the missing number in the sequence: 16, 18, ____, 22, 24.
20The sequence increases by 2 each step: 18 + 2 = 20.
5. Find the missing number in the sequence: 2, 4, ____, 8, 10.
6The sequence increases by 2 each step: 4 + 2 = 6.
6. Find the missing number in the sequence: 14, 16, ____, 20, 22.
18The sequence increases by 2 each step: 16 + 2 = 18.
7. Find the missing number in the sequence: 6, 8, ____, 12, 14.
10The sequence increases by 2 each step: 8 + 2 = 10.
8. Find the missing number in the sequence: 4, 5, ____, 7, 8.
6The sequence increases by 1 each step: 5 + 1 = 6.
9. Find the missing number in the sequence: 8, 9, ____, 11, 12.
10The sequence increases by 1 each step: 9 + 1 = 10.
10. Find the missing number in the sequence: 13, 14, ____, 16, 17.
15The sequence increases by 1 each step: 14 + 1 = 15.
11. Find the missing number in the sequence: 20, 25, ____, 35, 40.
30The sequence increases by 5 each step: 25 + 5 = 30.
12. Find the missing number in the sequence: 19, 20, ____, 22, 23.
21The sequence increases by 1 each step: 20 + 1 = 21.
12 questions · Seed 91 · 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: 18, 20, ____, 24, 26.
3. Find the missing number in the sequence: 19, 24, ____, 34, 39.
4. Find the missing number in the sequence: 16, 18, ____, 22, 24.
5. Find the missing number in the sequence: 2, 4, ____, 8, 10.
6. Find the missing number in the sequence: 14, 16, ____, 20, 22.
7. Find the missing number in the sequence: 6, 8, ____, 12, 14.
8. Find the missing number in the sequence: 4, 5, ____, 7, 8.
9. Find the missing number in the sequence: 8, 9, ____, 11, 12.
10. Find the missing number in the sequence: 13, 14, ____, 16, 17.
11. Find the missing number in the sequence: 20, 25, ____, 35, 40.
12. Find the missing number in the sequence: 19, 20, ____, 22, 23.
12 questions · Seed 91 · 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: 18, 20, ____, 24, 26.
22The sequence increases by 2 each step: 20 + 2 = 22.
3. Find the missing number in the sequence: 19, 24, ____, 34, 39.
29The sequence increases by 5 each step: 24 + 5 = 29.
4. Find the missing number in the sequence: 16, 18, ____, 22, 24.
20The sequence increases by 2 each step: 18 + 2 = 20.
5. Find the missing number in the sequence: 2, 4, ____, 8, 10.
6The sequence increases by 2 each step: 4 + 2 = 6.
6. Find the missing number in the sequence: 14, 16, ____, 20, 22.
18The sequence increases by 2 each step: 16 + 2 = 18.
7. Find the missing number in the sequence: 6, 8, ____, 12, 14.
10The sequence increases by 2 each step: 8 + 2 = 10.
8. Find the missing number in the sequence: 4, 5, ____, 7, 8.
6The sequence increases by 1 each step: 5 + 1 = 6.
9. Find the missing number in the sequence: 8, 9, ____, 11, 12.
10The sequence increases by 1 each step: 9 + 1 = 10.
10. Find the missing number in the sequence: 13, 14, ____, 16, 17.
15The sequence increases by 1 each step: 14 + 1 = 15.
11. Find the missing number in the sequence: 20, 25, ____, 35, 40.
30The sequence increases by 5 each step: 25 + 5 = 30.
12. Find the missing number in the sequence: 19, 20, ____, 22, 23.
21The sequence increases by 1 each step: 20 + 1 = 21.
12 questions · Seed 91 · Age guidance, not curriculum certification