1 HN user recommended this explainer1 month2020–2025score 1
Years with an HN recommendation, 2007–2026
HN links it to explain why people repeatedly get large-number arithmetic wrong in discussions of money and mental math.
Matt Parker of Stand-up Maths explains why people keep making the same mistake with millions and billions, using a Bloomberg cash calculator example. He looks at the unit slip behind the repeated arithmetic error.
“Here's a great explanation of what's probably happening” (HN, 2022)
This mistake is so interesting to me. Here's a great explanation of what's probably happening: [this video] tl;dr: mentally we take off "millions" as a unit, do the calculation, then add "millions" back on. This works for addition, subtraction, and inequality but fails for multiplication and division.
Explains the units mistake in mental arithmetic with millions
I'm not sure that there's a name for that kind of maths error, but there is a reason why people keep making it, as Matt Parker discusses: [this video] .
Explains why people repeatedly make this math error
Reminds me of this classic: [link] “Bloomberg spent $500 million on ads. The U.S. population is 327 million. He could have given each American $1 million and still have money left over.” [this video]
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