Small practice. Bright discoveries.Explore the free starter collection
Back to worksheets
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.

New variationTry interactive challengeBrowse templates

Choose “Save as PDF” to keep a copy. Use your browser’s paper setting for A4 or Letter.

Worksheet StudioPractice pack · Ages 4-6

Missing sequence terms

Take your time. Show your thinking.

  1. 1. Find the missing number in the sequence: 16, 21, ____, 31, 36.

    16+521+531+536+5?
  2. 2. Find the missing number in the sequence: 18, 20, ____, 24, 26.

    18+220+224+226+2?
  3. 3. Find the missing number in the sequence: 19, 24, ____, 34, 39.

    19+524+534+539+5?
  4. 4. Find the missing number in the sequence: 16, 18, ____, 22, 24.

    16+218+222+224+2?
  5. 5. Find the missing number in the sequence: 2, 4, ____, 8, 10.

    2+24+28+210+2?
  6. 6. Find the missing number in the sequence: 14, 16, ____, 20, 22.

    14+216+220+222+2?
  7. 7. Find the missing number in the sequence: 6, 8, ____, 12, 14.

    6+28+212+214+2?
  8. 8. Find the missing number in the sequence: 4, 5, ____, 7, 8.

    4+15+17+18+1?
  9. 9. Find the missing number in the sequence: 8, 9, ____, 11, 12.

    8+19+111+112+1?
  10. 10. Find the missing number in the sequence: 13, 14, ____, 16, 17.

    13+114+116+117+1?
  11. 11. Find the missing number in the sequence: 20, 25, ____, 35, 40.

    20+525+535+540+5?
  12. 12. Find the missing number in the sequence: 19, 20, ____, 22, 23.

    19+120+122+123+1?
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. 1. Find the missing number in the sequence: 16, 21, ____, 31, 36.

    26

    The sequence increases by 5 each step: 21 + 5 = 26.

  2. 2. Find the missing number in the sequence: 18, 20, ____, 24, 26.

    22

    The sequence increases by 2 each step: 20 + 2 = 22.

  3. 3. Find the missing number in the sequence: 19, 24, ____, 34, 39.

    29

    The sequence increases by 5 each step: 24 + 5 = 29.

  4. 4. Find the missing number in the sequence: 16, 18, ____, 22, 24.

    20

    The sequence increases by 2 each step: 18 + 2 = 20.

  5. 5. Find the missing number in the sequence: 2, 4, ____, 8, 10.

    6

    The sequence increases by 2 each step: 4 + 2 = 6.

  6. 6. Find the missing number in the sequence: 14, 16, ____, 20, 22.

    18

    The sequence increases by 2 each step: 16 + 2 = 18.

  7. 7. Find the missing number in the sequence: 6, 8, ____, 12, 14.

    10

    The sequence increases by 2 each step: 8 + 2 = 10.

  8. 8. Find the missing number in the sequence: 4, 5, ____, 7, 8.

    6

    The sequence increases by 1 each step: 5 + 1 = 6.

  9. 9. Find the missing number in the sequence: 8, 9, ____, 11, 12.

    10

    The sequence increases by 1 each step: 9 + 1 = 10.

  10. 10. Find the missing number in the sequence: 13, 14, ____, 16, 17.

    15

    The sequence increases by 1 each step: 14 + 1 = 15.

  11. 11. Find the missing number in the sequence: 20, 25, ____, 35, 40.

    30

    The sequence increases by 5 each step: 25 + 5 = 30.

  12. 12. Find the missing number in the sequence: 19, 20, ____, 22, 23.

    21

    The sequence increases by 1 each step: 20 + 1 = 21.

12 questions · Seed 91 · Age guidance, not curriculum certification