https://zeta.one/viral-math/

I wrote a (very long) blog post about those viral math problems and am looking for feedback, especially from people who are not convinced that the problem is ambiguous.

It’s about a 30min read so thank you in advance if you really take the time to read it, but I think it’s worth it if you joined such discussions in the past, but I’m probably biased because I wrote it :)

  • wischi@programming.devOP
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    1 year ago

    In a scientific context it’s actually very rare to run into that issue because divisions are mostly written as fractions which will completely mitigate the issue.

    The strong implicit multiplication will only cause ambiguity after a division with inline notation. Once you use fractions the ambiguity vanishes.

    In practice you also rarely see implicit multiplications between numbers but mostly between variables or variables and their coefficients.

    • DRx@lemmy.world
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      1 year ago

      Def not a math major (BS/PharmD), but your explanation was like seeing through a visual illusion for the first time! lol

      I was always taught PEMDAS growing up, and that the MD and the AS was read left to right in an equation like above. But stating the division as a fraction completely changes my mind now about how this calculation works. I think what would happen in a calculation I use every day if the former was used.

      Example: Cockcroft-Gault Equation (estimation of renal function)

      (140-age)(kg) / 72(SCr) vs (140-age) X kg ➗72 X SCr

      In the first eq (correct one) an 80yo patient who weighs 65kg and has an SCr ~ 1.5 = 36.11

      In the latter it = 81.25 (waaay too high for an 80yo lol)

      edit: calculation variable

    • MrMobius @sh.itjust.works
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      1 year ago

      Yes of course, we always used fractions so there was no ambiguity. Last time I saw the division symbol must have been in primary school!