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 :)

  • Spacehooks@reddthat.com
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    11 months ago

    This actually explains alot. Murica is Pemdas but Canadian used Bodmas so multiply is first in America.

    • ggppjj@lemmy.world
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      11 months ago

      As far as I understand it, they’re given equal weight in the order of operations, it’s just whichever you hit first left to right.

      • Spacehooks@reddthat.com
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        11 months ago

        Yeah 100% was not taught that. Follow the pemdas or fail the test. Division is after Multiply in pemdas.

        I put the equation into excel and get 9 which only makes sense in bodmas.

          • Spacehooks@reddthat.com
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            8 months ago

            The y(n+1) is same as yn + y if you removed the “6÷” part. It’s implied multiplication.

              • Spacehooks@reddthat.com
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                8 months ago

                Well I’m not seeing the difference here. Yn+y= yn+y = y(n+1) = y × (n +1) I think we agree with that.

                • 💡𝚂𝗆𝖺𝗋𝗍𝗆𝖺𝗇 𝙰𝗉𝗉𝗌📱@programming.dev
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                  8 months ago

                  Ok, that’s a start. In your simple example they are all equal, but they aren’t all the same.

                  yn+y - 2 terms

                  y(n+1) - 1 term

                  y×(n +1) - 2 terms

                  To see the difference, now precede it with a division, like in the original question…

                  1÷yn+y=(1/yn)+y

                  1÷y(n+1)=1/(yn+y)

                  1÷y×(n +1)=(n +1)/y

                  Note that in the last one, compared to the second one, the (n+1) is now in the numerator instead of in the denominator. Welcome to why having the (2+2) in the numerator gives the wrong answer.

                  • Spacehooks@reddthat.com
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                    8 months ago

                    Good example wish we had better math format.
                    The granger issue is I thought multiple always happens first. But apparently it’s what’s left side first.