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Grade 1 · Math · Building Confidence

Free Missing Addends Within 20 worksheet - version 1

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 · Building confidence · 12 questions · Version PG-IQDSEQ-RBT8

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

__ + 15 = 15

2.

__ + 13 = 20

3.

__ + 3 = 20

4.

__ + 5 = 18

5.

__ + 4 = 20

6.

__ + 10 = 18

7.

__ + 6 = 20

8.

__ + 1 = 20

9.

__ + 2 = 20

10.

__ + 1 = 2

11.

__ + 15 = 20

12.

__ + 17 = 20

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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 1
  1. __ + 15 = 150
  2. __ + 13 = 207
  3. __ + 3 = 2017
  4. __ + 5 = 1813
  5. __ + 4 = 2016
  6. __ + 10 = 188
  7. __ + 6 = 2014
  8. __ + 1 = 2019
  9. __ + 2 = 2018
  10. __ + 1 = 21
  11. __ + 15 = 205
  12. __ + 17 = 203

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.