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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: 9, 17, ____, 33, 41.
2. Find the missing number in the sequence: 19, 26, ____, 40, 47.
3. Find the missing number in the sequence: 16, 24, ____, 40, 48.
4. Find the missing number in the sequence: 6, 12, ____, 24, 30.
5. Find the missing number in the sequence: 9, 12, ____, 18, 21.
6. Find the missing number in the sequence: 11, 18, ____, 32, 39.
7. Find the missing number in the sequence: 10, 13, ____, 19, 22.
8. Find the missing number in the sequence: 10, 20, ____, 40, 50.
9. Find the missing number in the sequence: 7, 11, ____, 19, 23.
10. Find the missing number in the sequence: 8, 11, ____, 17, 20.
11. Find the missing number in the sequence: 17, 27, ____, 47, 57.
12. Find the missing number in the sequence: 17, 25, ____, 41, 49.
12 questions · Seed 61 · 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: 9, 17, ____, 33, 41.
25The sequence increases by 8 each step: 17 + 8 = 25.
2. Find the missing number in the sequence: 19, 26, ____, 40, 47.
33The sequence increases by 7 each step: 26 + 7 = 33.
3. Find the missing number in the sequence: 16, 24, ____, 40, 48.
32The sequence increases by 8 each step: 24 + 8 = 32.
4. Find the missing number in the sequence: 6, 12, ____, 24, 30.
18The sequence increases by 6 each step: 12 + 6 = 18.
5. Find the missing number in the sequence: 9, 12, ____, 18, 21.
15The sequence increases by 3 each step: 12 + 3 = 15.
6. Find the missing number in the sequence: 11, 18, ____, 32, 39.
25The sequence increases by 7 each step: 18 + 7 = 25.
7. Find the missing number in the sequence: 10, 13, ____, 19, 22.
16The sequence increases by 3 each step: 13 + 3 = 16.
8. Find the missing number in the sequence: 10, 20, ____, 40, 50.
30The sequence increases by 10 each step: 20 + 10 = 30.
9. Find the missing number in the sequence: 7, 11, ____, 19, 23.
15The sequence increases by 4 each step: 11 + 4 = 15.
10. Find the missing number in the sequence: 8, 11, ____, 17, 20.
14The sequence increases by 3 each step: 11 + 3 = 14.
11. Find the missing number in the sequence: 17, 27, ____, 47, 57.
37The sequence increases by 10 each step: 27 + 10 = 37.
12. Find the missing number in the sequence: 17, 25, ____, 41, 49.
33The sequence increases by 8 each step: 25 + 8 = 33.
12 questions · Seed 61 · 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: 9, 17, ____, 33, 41.
2. Find the missing number in the sequence: 19, 26, ____, 40, 47.
3. Find the missing number in the sequence: 16, 24, ____, 40, 48.
4. Find the missing number in the sequence: 6, 12, ____, 24, 30.
5. Find the missing number in the sequence: 9, 12, ____, 18, 21.
6. Find the missing number in the sequence: 11, 18, ____, 32, 39.
7. Find the missing number in the sequence: 10, 13, ____, 19, 22.
8. Find the missing number in the sequence: 10, 20, ____, 40, 50.
9. Find the missing number in the sequence: 7, 11, ____, 19, 23.
10. Find the missing number in the sequence: 8, 11, ____, 17, 20.
11. Find the missing number in the sequence: 17, 27, ____, 47, 57.
12. Find the missing number in the sequence: 17, 25, ____, 41, 49.
12 questions · Seed 61 · 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: 9, 17, ____, 33, 41.
25The sequence increases by 8 each step: 17 + 8 = 25.
2. Find the missing number in the sequence: 19, 26, ____, 40, 47.
33The sequence increases by 7 each step: 26 + 7 = 33.
3. Find the missing number in the sequence: 16, 24, ____, 40, 48.
32The sequence increases by 8 each step: 24 + 8 = 32.
4. Find the missing number in the sequence: 6, 12, ____, 24, 30.
18The sequence increases by 6 each step: 12 + 6 = 18.
5. Find the missing number in the sequence: 9, 12, ____, 18, 21.
15The sequence increases by 3 each step: 12 + 3 = 15.
6. Find the missing number in the sequence: 11, 18, ____, 32, 39.
25The sequence increases by 7 each step: 18 + 7 = 25.
7. Find the missing number in the sequence: 10, 13, ____, 19, 22.
16The sequence increases by 3 each step: 13 + 3 = 16.
8. Find the missing number in the sequence: 10, 20, ____, 40, 50.
30The sequence increases by 10 each step: 20 + 10 = 30.
9. Find the missing number in the sequence: 7, 11, ____, 19, 23.
15The sequence increases by 4 each step: 11 + 4 = 15.
10. Find the missing number in the sequence: 8, 11, ____, 17, 20.
14The sequence increases by 3 each step: 11 + 3 = 14.
11. Find the missing number in the sequence: 17, 27, ____, 47, 57.
37The sequence increases by 10 each step: 27 + 10 = 37.
12. Find the missing number in the sequence: 17, 25, ____, 41, 49.
33The sequence increases by 8 each step: 25 + 8 = 33.
12 questions · Seed 61 · Age guidance, not curriculum certification