this post was submitted on 17 Jul 2024
256 points (93.2% liked)

Showerthoughts

29805 readers
862 users here now

A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. A showerthought should offer a unique perspective on an ordinary part of life.

Rules

  1. All posts must be showerthoughts
  2. The entire showerthought must be in the title
  3. Avoid politics
    • 3.1) NEW RULE as of 5 Nov 2024, trying it out
    • 3.2) Political posts often end up being circle jerks (not offering unique perspective) or enflaming (too much work for mods).
    • 3.3) Try c/politicaldiscussion, volunteer as a mod here, or start your own community.
  4. Posts must be original/unique
  5. Adhere to Lemmy's Code of Conduct

founded 1 year ago
MODERATORS
 

Amazon is running a Prime Day sale on July 16 and 17. Setting aside the fact that this is two separate days, neither 716 nor 717 are prime numbers. They should've done 7/19 instead.

you are viewing a single comment's thread
view the rest of the comments
[โ€“] Audacious 2 points 4 months ago (1 children)

Back in the olden days before digital calculators, people had tricks like that to help them do mental math.

[โ€“] FeatherConstrictor 1 points 4 months ago

๐Ÿ˜‚ I'm familiar with many of them because I liked math in school and went through all of primary and middle school without a digital calculator. This one is one I hadn't heard of before and, again because I like math, I'm interested in understanding 1) what the trick is and 2) mathematically how it works out