Library›Addition Fluency›One card

A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaSum

20 + 25

Think it. Then flip it. ahamoraTap to reveal Back to the cue
Math & LogicOne small aha
Your new aha45

20 + 25 = 45. Changing the order gives 25 + 20, 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. 43720 + 26RECALL
    46

    Mental addition

    Open this card ↗
  2. 43820 + 27RECALL
    47

    Mental addition

    Open this card ↗
  3. 43920 + 28RECALL
    48

    Mental addition

    Open this card ↗