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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 7-9
Missing sequence terms
Take your time. Show your thinking.
1. Find the missing number in the sequence: 6, 10, ____, 18, 22.
2. Find the missing number in the sequence: 5, 11, ____, 23, 29.
3. Find the missing number in the sequence: 18, 28, ____, 48, 58.
4. Find the missing number in the sequence: 15, 25, ____, 45, 55.
5. Find the missing number in the sequence: 5, 12, ____, 26, 33.
6. Find the missing number in the sequence: 1, 5, ____, 13, 17.
7. Find the missing number in the sequence: 3, 7, ____, 15, 19.
8. Find the missing number in the sequence: 3, 9, ____, 21, 27.
9. Find the missing number in the sequence: 7, 14, ____, 28, 35.
10. Find the missing number in the sequence: 14, 21, ____, 35, 42.
11. Find the missing number in the sequence: 10, 14, ____, 22, 26.
12. Find the missing number in the sequence: 19, 28, ____, 46, 55.
12 questions · Seed 53 · Age guidance, not curriculum certification
View the answer key
Worksheet StudioAnswer key · Ages 7-9
Missing sequence terms
Answers and reasoning. Review before teaching.
1. Find the missing number in the sequence: 6, 10, ____, 18, 22.
14The sequence increases by 4 each step: 10 + 4 = 14.
2. Find the missing number in the sequence: 5, 11, ____, 23, 29.
17The sequence increases by 6 each step: 11 + 6 = 17.
3. Find the missing number in the sequence: 18, 28, ____, 48, 58.
38The sequence increases by 10 each step: 28 + 10 = 38.
4. Find the missing number in the sequence: 15, 25, ____, 45, 55.
35The sequence increases by 10 each step: 25 + 10 = 35.
5. Find the missing number in the sequence: 5, 12, ____, 26, 33.
19The sequence increases by 7 each step: 12 + 7 = 19.
6. Find the missing number in the sequence: 1, 5, ____, 13, 17.
9The sequence increases by 4 each step: 5 + 4 = 9.
7. Find the missing number in the sequence: 3, 7, ____, 15, 19.
11The sequence increases by 4 each step: 7 + 4 = 11.
8. Find the missing number in the sequence: 3, 9, ____, 21, 27.
15The sequence increases by 6 each step: 9 + 6 = 15.
9. Find the missing number in the sequence: 7, 14, ____, 28, 35.
21The sequence increases by 7 each step: 14 + 7 = 21.
10. Find the missing number in the sequence: 14, 21, ____, 35, 42.
28The sequence increases by 7 each step: 21 + 7 = 28.
11. Find the missing number in the sequence: 10, 14, ____, 22, 26.
18The sequence increases by 4 each step: 14 + 4 = 18.
12. Find the missing number in the sequence: 19, 28, ____, 46, 55.
37The sequence increases by 9 each step: 28 + 9 = 37.
12 questions · Seed 53 · Age guidance, not curriculum certification
Worksheet StudioPractice pack · Ages 7-9
Missing sequence terms
Take your time. Show your thinking.
1. Find the missing number in the sequence: 6, 10, ____, 18, 22.
2. Find the missing number in the sequence: 5, 11, ____, 23, 29.
3. Find the missing number in the sequence: 18, 28, ____, 48, 58.
4. Find the missing number in the sequence: 15, 25, ____, 45, 55.
5. Find the missing number in the sequence: 5, 12, ____, 26, 33.
6. Find the missing number in the sequence: 1, 5, ____, 13, 17.
7. Find the missing number in the sequence: 3, 7, ____, 15, 19.
8. Find the missing number in the sequence: 3, 9, ____, 21, 27.
9. Find the missing number in the sequence: 7, 14, ____, 28, 35.
10. Find the missing number in the sequence: 14, 21, ____, 35, 42.
11. Find the missing number in the sequence: 10, 14, ____, 22, 26.
12. Find the missing number in the sequence: 19, 28, ____, 46, 55.
12 questions · Seed 53 · Age guidance, not curriculum certification
Worksheet StudioAnswer key · Ages 7-9
Missing sequence terms
Answers and reasoning. Review before teaching.
1. Find the missing number in the sequence: 6, 10, ____, 18, 22.
14The sequence increases by 4 each step: 10 + 4 = 14.
2. Find the missing number in the sequence: 5, 11, ____, 23, 29.
17The sequence increases by 6 each step: 11 + 6 = 17.
3. Find the missing number in the sequence: 18, 28, ____, 48, 58.
38The sequence increases by 10 each step: 28 + 10 = 38.
4. Find the missing number in the sequence: 15, 25, ____, 45, 55.
35The sequence increases by 10 each step: 25 + 10 = 35.
5. Find the missing number in the sequence: 5, 12, ____, 26, 33.
19The sequence increases by 7 each step: 12 + 7 = 19.
6. Find the missing number in the sequence: 1, 5, ____, 13, 17.
9The sequence increases by 4 each step: 5 + 4 = 9.
7. Find the missing number in the sequence: 3, 7, ____, 15, 19.
11The sequence increases by 4 each step: 7 + 4 = 11.
8. Find the missing number in the sequence: 3, 9, ____, 21, 27.
15The sequence increases by 6 each step: 9 + 6 = 15.
9. Find the missing number in the sequence: 7, 14, ____, 28, 35.
21The sequence increases by 7 each step: 14 + 7 = 21.
10. Find the missing number in the sequence: 14, 21, ____, 35, 42.
28The sequence increases by 7 each step: 21 + 7 = 28.
11. Find the missing number in the sequence: 10, 14, ____, 22, 26.
18The sequence increases by 4 each step: 14 + 4 = 18.
12. Find the missing number in the sequence: 19, 28, ____, 46, 55.
37The sequence increases by 9 each step: 28 + 9 = 37.
12 questions · Seed 53 · Age guidance, not curriculum certification