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Grade 1 · Math · Challenge

Free Missing Addends Within 20 worksheet - version 16

Find the missing part in addition equations through 20. This printable version includes 12 grade-appropriate questions and a separate answer sheet.

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Missing Addends Within 20

Grade 1 · Stretch challenge · 12 questions · Version PG-15BBXRU-1OAJ

Four children and a teacher collaborate with blocks, patterns, and a notebook.
1.

__ + 2 = 18

2.

__ + 7 = 12

3.

__ + 2 = 5

4.

__ + 1 = 12

5.

__ + 3 = 20

6.

__ + 8 = 17

7.

__ + 9 = 17

8.

__ + 0 = 20

9.

__ + 0 = 7

10.

__ + 15 = 20

11.

__ + 7 = 20

12.

__ + 1 = 1

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Answers and teaching notes

Use the answers to check the work after the learner finishes. For writing prompts, the guide describes what a strong response should include.

Show answers for version 16
  1. __ + 2 = 1816
  2. __ + 7 = 125
  3. __ + 2 = 53
  4. __ + 1 = 1211
  5. __ + 3 = 2017
  6. __ + 8 = 179
  7. __ + 9 = 178
  8. __ + 0 = 2020
  9. __ + 0 = 77
  10. __ + 15 = 205
  11. __ + 7 = 2013
  12. __ + 1 = 10

Worked example

__ + 6 = 14. Think 14 - 6, so the missing addend is 8.

Common mistake

Adding the known addend and total together.

Helpful hint

Subtract the known part from the total.