PencilGoPencilGo

Missing Addends Within 20

Grade 1 · Building confidence · 12 questions · Version PG-TS153T-RBT8

1.

__ + 8 = 20

2.

__ + 2 = 20

3.

__ + 3 = 20

4.

__ + 1 = 5

5.

__ + 13 = 20

6.

__ + 0 = 10

7.

__ + 5 = 10

8.

__ + 3 = 6

9.

__ + 9 = 20

10.

__ + 5 = 20

11.

__ + 11 = 13

12.

__ + 7 = 12

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 11
  1. __ + 8 = 2012
  2. __ + 2 = 2018
  3. __ + 3 = 2017
  4. __ + 1 = 54
  5. __ + 13 = 207
  6. __ + 0 = 1010
  7. __ + 5 = 105
  8. __ + 3 = 63
  9. __ + 9 = 2011
  10. __ + 5 = 2015
  11. __ + 11 = 132
  12. __ + 7 = 125

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.