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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    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.

    • multiple always happens first. But apparently it’s what’s left side first

      Multiplication and division are equal precedence (and done left to right) if that’s what you’re talking about, but the issue is that a(b+c) isn’t “multiplication” at all, it’s a bracketed term with a coefficient which is therefore subject to The Distributive Law, and is solved as part of solving Brackets, which is always first. Multiplication refers literally to multiplication signs, of which there are none in the original question. A Term is a product, which is the result of a multiplication, not something which is to be multiplied.

      If a=2 and b=3, then…

      axb=2x3 - 2 terms

      ab=6 - 1 term

      • Spacehooks@reddthat.com
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        8 months ago

        That is what I am talking about. I would have got 1 by doing 2(2+2) = 8 first. Not because of bracket but because of “implied multiplication.”

        What I am learning here: 8÷2(2+2) is not same as 8÷2×(2+2)

        For several reasons:

        1. number next bracket is not the same as normal multiplication in rule book
        2. ÷ & × have right of way rule with whoever is left most wins.
        • I would have got 1 by doing 2(2+2) = 8 first. Not because of bracket but because of “implied multiplication.”

          Yeah, right answer but wrong reason. There’s no such thing as implicit multiplication.

          What I am learning here: 8÷2(2+2) is not same as 8÷2×(2+2)

          Correct, and that’s because of Terms - 8÷2(2+2) is 2 terms, with the (2+2) in the denominator, but 8÷2×(2+2) is 3 terms, with the (2+2) in the numerator… hence why people get the wrong answer when they add an extra multiply in.

          number next bracket is not the same as normal multiplication in rule book

          Right, because it’s not “multiplication” at all (only applies literally to multiplication signs), it’s a coefficient of a bracketed term, which means we have to apply The Distributive Law as part of solving Brackets.

          ÷ & × have right of way rule with whoever is left most wins

          Yeah, the actual rule is Left associativity, and going left to right is the easy way to obey that.