• Sockenklaus
    link
    38 months ago

    You clearly mean:

    14: 1 + 8 = 9 (not db 7)

    Someone else in this thread correctly stated:

    “Chop of last digit, double it and subtract from what is left”

    14: 1 - 8 = -7. (dB 7!)

    Math is awesome, I didn’t know this trick!

    • @BruceDoh
      link
      18 months ago

      Yes, that’s what I meant. The subtract rule works.