Library›Addition Fluency›One card

A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaSum

9 + 28

Think it. Then flip it. ahamoraTap to reveal Back to the cue
Math & LogicOne small aha
Your new aha37

9 + 28 = 37. Changing the order gives 28 + 9, 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. 2949 + 29RECALL
    38

    Mental addition

    Open this card ↗
  2. 2959 + 30RECALL
    39

    Mental addition

    Open this card ↗
  3. 29610 + 20RECALL
    30

    Mental addition

    Open this card ↗