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Grade 1 · Math · Challenge

Free Missing Addends Within 20 worksheet - version 18

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-11FHI28-1OAJ

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

__ + 3 = 8

2.

__ + 13 = 20

3.

__ + 7 = 13

4.

__ + 12 = 18

5.

__ + 8 = 20

6.

__ + 9 = 20

7.

__ + 6 = 14

8.

__ + 6 = 20

9.

__ + 7 = 20

10.

__ + 9 = 17

11.

__ + 1 = 20

12.

__ + 8 = 12

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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 18
  1. __ + 3 = 85
  2. __ + 13 = 207
  3. __ + 7 = 136
  4. __ + 12 = 186
  5. __ + 8 = 2012
  6. __ + 9 = 2011
  7. __ + 6 = 148
  8. __ + 6 = 2014
  9. __ + 7 = 2013
  10. __ + 9 = 178
  11. __ + 1 = 2019
  12. __ + 8 = 124

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.