Skip to content
LessonPrint

Subtraction as Missing Part — to 20 is a free printable Grade 1 maths worksheet on reaching a subtraction through the addition fact, past ten, aligned to Common Core standard 1.OA.B.4. It prints 12 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two pupils in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.

Set 17 of 25 · the same problems every time you open this link.

Next setLesson plan

One paper per pupil

12345678910111213141516171819202122232425

Set 1 has all 25 in a single PDF. All 25 sets ask different questions.

Subtraction as Missing Part — to 20

1.OA.B.4

NameDate

Fill in both blanks.

1.4 + ___ = 24 , so 24 − 4 = ___
2.10 + ___ = 25 , so 25 − 10 = ___
3.15 + ___ = 25 , so 25 − 15 = ___
4.2 + ___ = 19 , so 19 − 2 = ___
5.18 + ___ = 22 , so 22 − 18 = ___
6.18 + ___ = 23 , so 23 − 18 = ___
7.1 + ___ = 20 , so 20 − 1 = ___
8.10 + ___ = 22 , so 22 − 10 = ___
9.7 + ___ = 20 , so 20 − 7 = ___
10.13 + ___ = 22 , so 22 − 13 = ___
11.6 + ___ = 21 , so 21 − 6 = ___
12.4 + ___ = 21 , so 21 − 4 = ___

LessonPrint · 1.OA.B.4 · Set 17 · free to copy for classroom use

Answer key — Subtraction as Missing Part — to 20

Set 17. Prints on its own sheet.

  1. 1.20 and 20
  2. 2.15 and 15
  3. 3.10 and 10
  4. 4.17 and 17
  5. 5.4 and 4
  6. 6.5 and 5
  7. 7.19 and 19
  8. 8.12 and 12
  9. 9.13 and 13
  10. 10.9 and 9
  11. 11.15 and 15
  12. 12.17 and 17

More practice for 1.OA.B.4

See subtraction as finding the missing part.

Teaching this next? Subtraction as a Missing Part is the 40-minute plan for it, with the misconceptions to expect.

All Grade 1 worksheets

Last reviewed 2026-09-05. Aligned to 1.OA.B.4 of the Common Core State Standards for mathematics.