Library›Multiplication Fluency›One card

A LITTLE SOMETHING WORTH KNOWING

A small discovery. Yours to pass on.

Math & LogicOne small ahaProduct

18 × 5

Think it. Then flip it. ahamoraTap to reveal Back to the cue
Math & LogicOne small aha
Your new aha90

18 groups of 5 make 90. Reversing the factors, 5 × 18, gives the same product. Source: Multiplication table ↗

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 Multiplication Fluency

A few more worth knowing.

  1. 30918 × 6RECALL
    108

    Mental multiplication

    Open this card ↗
  2. 31018 × 7RECALL
    126

    Mental multiplication

    Open this card ↗
  3. 31118 × 8RECALL
    144

    Mental multiplication

    Open this card ↗