Library›Addition Fluency›One card

A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaSum

3 + 9

Think it. Then flip it. ahamoraTap to reveal Back to the cue
Math & LogicOne small aha
Your new aha12

3 + 9 = 12. Changing the order gives 9 + 3, the same sum. Source: Addition ↗

ahamoraReference ↗

Keep the thread going

One answer is a beginning.

Share a little curiosity, or follow it into the full collection.

Flip the full deck →

More from Addition Fluency

A few more worth knowing.

  1. 643 + 10RECALL
    13

    Mental addition

    Open this card ↗
  2. 653 + 11RECALL
    14

    Mental addition

    Open this card ↗
  3. 663 + 12RECALL
    15

    Mental addition

    Open this card ↗