• bisby@lemmy.world
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    6 months ago

    I hate how these things always come up because “order of operations!” It’s mostly people who are bad at math remembering one topic they struggled with and finally got right, and now they know it’s a touchy subject so it will drive engagement. It’s the modern equivalent of “Mathematicians hate this one secret for solving equations! Click to find out!” Pure engagement bait.

    But in all the engineering ive done, things never really come up like this. If there is any potential clarity issues, parentheses would be used, or it would be formatted in a way that makes it much more clear.

    40 - (32/2), or 40 - ³²⁄₂ has no clarity issues imo. You don’t even have to think about order of operations because 32 halves is a number on its own. it isn’t an “operation” to do necessarily, it’s a fraction to reduce.

    And yes, I get the joke. The joke is making fun of the engagement bait of “some people will get the order of operations wrong!”

    The joke

    (40 - 32)/2 = 4

    If you stop here, you used the wrong order of operations. This is where the the fights normally start in the replies.

    but the kid said “4!” not “4”

    40 - (32/2) = 24 = 4 * 3 * 2 * 1 = 4!

    • jjjalljs@ttrpg.network
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      6 months ago

      s. If there is any potential clarity issues, parentheses would be used, or it would be formatted in a way that makes it much more clear.

      It reminds me of a very old xkcd that posits "communicating badly and acting smug when you’re misunderstood is not cleverness "

      https://xkcd.com/169/

    • AwkwardLookMonkeyPuppet@lemmy.world
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      6 months ago

      It’s the same as “only 2% of people get this right! If you get it right you have a very strong brain!”. It’s just a little more devious about it.

      • gregorum@lemm.ee
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        6 months ago

        Exactly. if only 2% of people get it, perhaps you’re just shitty at communicating.

    • Ballistic_86@lemmy.world
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      6 months ago

      It does leave ambiguity with it being an, apparent, quote/dialogue. Correct and Incorrect are both correct depending on your POV and how you interpret social media posts

    • MBM@lemmings.world
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      6 months ago

      This one’s perfectly unambiguous without brackets, unlike the 1/2x stuff

      • Ender of Games@sh.itjust.works
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        6 months ago

        Even your “BODMAS” isn’t universal, lots of people learn “PEMDAS” or “BEDMAS”

        At any level of mathematics after elementary school, you never see terrible expressions like this. Well, except for facebook and twitter

        Take for example: 2/2*2 It is 0.5 or 2 depending on order. But if I were anything after high school (I was more complacent in high school, I guess) if someone gave me an arbitrarily solved equation or expression like this, I would be livid and raise hell at them for trying to do that.

        • Even your “BODMAS” isn’t universal, lots of people learn “PEMDAS” or “BEDMAS”

          The rules are universal, only the mnemonics used to remember the rules are different

          except for facebook and twitter

          … and high school Maths textbooks, and order of operations worksheet generators, and…

          2/2*2 It is 0.5 or 2 depending on order.

          It’s always 2. #MathsIsNeverAmbiguous

          • Ender of Games@sh.itjust.works
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            6 months ago

            Yes, the fundamentals the same, higher orders come first. BUT

            -Multiplication comes before division in some forms, like PEMDAS. In the example I use, this changes the answer.

            -When you apply an operation, you should specify what it is operating on. In all of these acronyms, addition comes before subtraction, but with a different example:

            2 - 2 + 2

            The minus sign only applies to the middle term, by convention. It is the equivalent of “adding negative two”. You can quickly see that this expression is equal to 2.

            But if you use one of these acronyms, you end with this expression evaluating to -2. I would say it is almost universally accepted that 2 is the correct answer, and -2 is incorrect. Basically, all these acronyms end up being useless waste of time.

            I don’t know if I conveyed this the first time, but, as a lover of pure mathematics, this is something that does not have application in life or in study. It’s an utterly useless waste of time. There is never a case where someone give you numbers like this, where it is not clear what order the numbers should be applied in.

            • Multiplication comes before division in some forms, like PEMDAS. In the example I use, this changes the answer

              If you have both multiplication and division then you do them left to right. PEMDAS doesn’t mean multiplication first, nor does BEDMAS mean division first. It’s PE(MD)(AS) and BE(DM)(AS) where the bracketed parts are done left to right.

              you should specify what it is operating on

              Left associativity means it always operates on the following term. i.e. terms are associated with the sign on their left.

              The minus sign only applies to the middle term, by convention

              By the rule of left associativity.

              But if you use one of these acronyms, you end with this expression evaluating to -2

              No it doesn’t. How on Earth did you manage to get -2?

              all these acronyms end up being useless waste of time

              No they’re not, but I don’t know yet where you’re going wrong with them without seeing your working out.

      • Leviathan@lemmy.world
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        6 months ago

        It’s perfectly reasonable to read this as both (40-32)/2 and 40-(32/2) anywhere past basic math.

  • Scary le Poo@beehaw.org
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    6 months ago

    Intentionally writing equations shittily is a special type of brain rot.

    40 - (32 / 2) = ?

    Ftfy.

  • Resol van Lemmy@lemmy.world
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    6 months ago

    I actually remember seeing this on my YouTube feed. I was pretty confused at first until I saw the factorial sign.

  • lurch (he/him)@sh.itjust.works
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    6 months ago

    it’s wrong, because:

    • i would never ask a kid something like that
    • there is a question mark missing
    • i don’t know any kids and they would probably just flip me off in that situation, which is okay, because they shouldn’t talk to strangers