Addition and subtraction within 20 · seed 1 · A4, ink-friendly. The answer key prints on its own page for grown-ups.

Bridging through ten

Mathematics · Addition & Subtraction · ages 6-7
Name ______________________   Date ____________

  1. 13 − 4. First, how many do you take away to reach 10?

    012345678910111213
    • 2
    • 3
    • 4

  2. What is 13 - 4?

    • 8
    • 10
    • 11
    • 9

  3. What is 9 + 5?

    Answer: ______________

  4. 8 + 6. First, how many do you add to 8 to make 10?

    012345678910
    • 1
    • 2
    • 4

  5. Mia works out 12 - 5 by doing 12 - 2 - 3. She gets 10, then 7. Is Mia right?

    Circle one:   True   False

  6. What is 7 + 8?

    • 15
    • 14
    • 16
    • 13

  7. What is 15 - 7?

    Answer: ______________

  8. You know 9 + 3 = 12. What is 12 − 3?

    • 9
    • 12
    • 3

  9. Leo solves 15 − 6 like this: 15 − 5 − 1 = 9. Did he split the 6 correctly?

    02469101215-5-1
    • No, he should have taken away 6 all at once
    • No, 5 + 1 does not equal 6
    • Yes, 5 + 1 = 6, so it works

  10. Tom says 9 + 7 = 15. Is Tom right?

    Circle one:   True   False

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Answer key

For grown-ups. Fold this page away before handing over the rest.

Bridging through ten W1-mt_m1W6nTQJ2b-s1

  1. 3 · 13 needs 3 taken away to land on 10. Then take away 1 more.
  2. 9 · Take 3 to reach 10, then 1 more, so 13 - 3 - 1 = 9.
  3. 14 · 9 needs 1 to make 10, leaving 4, so 10 + 4 = 14.
  4. 2 · 8 needs 2 more to reach 10. Then you still have 4 left over from the 6.
  5. True · Mia is right: 12 - 2 = 10 and 10 - 3 = 7, and 12 - 5 = 7.
  6. 15 · 7 needs 3 to make 10, leaving 5, so 10 + 5 = 15.
  7. 8 · 15 - 5 = 10, then 2 more makes 8.
  8. 9 · 12 − 3 = 9, the partner fact of 9 + 3 = 12.
  9. Yes, 5 + 1 = 6, so it works · 5 + 1 = 6, and 15 − 5 = 10, then 10 − 1 = 9. His method gives the right answer.
  10. False · Tom is wrong: 9 + 1 + 6 = 16, so 9 + 7 = 16.
Worksheet · LightMySky