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

Speedy facts within 20

Mathematics · Addition & Subtraction · ages 7-8
Name ______________________   Date ____________

  1. What is 14 − 6?

    • 7
    • 8
    • 9

  2. What is 5 + 7?

    • 12
    • 11
    • 13
    • 10

  3. Knowing 7 + 8 = 15 helps you know that 15 - 8 = 7.

    Circle one:   True   False

  4. What is 6 + 7?

    • 13
    • 12
    • 14

  5. What is 15 − 7?

    • 8
    • 7
    • 9

  6. What is 7 + 4?

    Answer: ______________

  7. You know 7 + 9 = 16. What is 16 - 9?

    • 6
    • 7
    • 8
    • 9

  8. What is 13 - 5?

    Answer: ______________

  9. Zoe knows 6 + 8 = 14. She wants 14 − 8 fast. What should she do?

    • Check a different double before solving the subtraction
    • Recall 6 + 8 = 14, so 14 - 8 = 6
    • Count back from 14 one step at a time

  10. Sam takes 10 seconds and uses his fingers to solve 7 + 6. Is Sam showing fluency with this fact?

    • Yes, because he got the correct answer even though he counted slowly
    • Yes, a fact is fluent whenever the final answer is correct
    • No, fluent recall is quick and does not use counting
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Answer key

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

Speedy facts within 20 W1-mt__t4afSyZRm-s1

  1. 8 · 14 − 6 = 8. Think: 6 + 8 = 14.
  2. 12 · 5 + 5 makes 10, and there are 2 more from the 7, so 10 + 2 = 12.
  3. True · The same three numbers make a fact family. Taking 8 from the whole 15 leaves the other part, 7.
  4. 13 · 6 + 7 is one less than 7 + 7 (14), so it is 13.
  5. 8 · 15 − 7 = 8. Think: 7 + 8 = 15.
  6. 11 · Use 7 + 3 = 10, then add the 1 left from 4. The answer is 11.
  7. 7 · The fact family has parts 7 and 9 and whole 16. Taking away 9 leaves 7.
  8. 8 · Take away 3 to reach 10, then take away 2 more. That leaves 8.
  9. Recall 6 + 8 = 14, so 14 - 8 = 6 · Since 6 + 8 = 14, she can jump straight to 14 − 8 = 6 without counting.
  10. No, fluent recall is quick and does not use counting · Getting the right answer is not enough. Fluency means fast recall, without needing to count.
Worksheet · LightMySky