LibraryAddition FluencyOne card

A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaSum

3 + 13

Think it. Then flip it.
ahamoraTap to reveal
Back to the cue
Math & LogicOne small aha
Your new aha16

3 + 13 = 16. Changing the order gives 13 + 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. 683 + 14RECALL
    17

    Mental addition

    Open this card ↗
  2. 693 + 15RECALL
    18

    Mental addition

    Open this card ↗
  3. 703 + 16RECALL
    19

    Mental addition

    Open this card ↗