Library›Subtraction Fluency›One card

A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaDifference

20 − 20

Think it. Then flip it. ahamoraTap to reveal Back to the cue
Math & LogicOne small aha
Your new aha0

20 − 20 = 0. The difference tells you the gap between 20 and 20. Source: Subtraction ↗

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 Subtraction Fluency

A few more worth knowing.

  1. 21220 − 19RECALL
    1

    Mental subtraction

    Open this card ↗
  2. 21320 − 18RECALL
    2

    Mental subtraction

    Open this card ↗
  3. 21420 − 17RECALL
    3

    Mental subtraction

    Open this card ↗