• SSUPII@sopuli.xyz
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    1 day ago

    I feel like I am getting trolled

    Isn’t 17 the actual right answer?

    • marcos@lemmy.world
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      18 hours ago

      Some people insist there’s no “correct” order for the basic arithmetic operations. And worse, some people insist the correct order is parenthesis first, then left to right.

      Both of those sets of people are wrong.

      • SkyeStarfall@lemmy.blahaj.zone
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        5 hours ago

        I mean, arithmetic order is just convention, not a mathematical truth. But that convention works in the way we know, yes, because that’s what’s… well… convention

        • marcos@lemmy.world
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          3 hours ago

          Social conventions are real, well defined things. Some mathematicians like to pretend they aren’t, while using a truckload of them; that’s a hypocritical opinion.

          That’s not to say you can’t change them. But all of basic arithmetic is a social convention, you can redefine the numbers and operations any time you want too.

      • MotoAsh@piefed.social
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        14 hours ago

        Hopefully you can see where their confusion might come from, though. PEMDAS is more P-E-MD-AS. If you have a bunch of unparenthesized addition and subtraction, left to right is correct. A lot of like, firstgrader math problems are just basic problems that are usually left to right (but should have some extras to highlight PEMDAS somewhere I’d hope).

        So they’re mostly telling you they only remember as much math as a small child that barely passed math exercizes.

        • orbitz@lemmy.ca
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          7 hours ago

          Huh I just remembered the orders of arithmetic but parentheses trump all so do them first (I use them in even the calculator app). Mean I assume that’s that that says but never learned that acronym is all. Now figuring out categories of words;really does my noodle in sometimes. Cause some words can be either depending on context. Math when it’s written out has (mostly) the same answer. I say mostly because somewhere in the back of my brain there are some scenarios where something more complicated than straight arithmetic can come out oddly but written as such should come out the same.

        • DefederateLemmyMl@feddit.nl
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          10 hours ago

          If you have a bunch of unparenthesized addition and subtraction, left to right is correct

          If you have a bunch of unparenthesized addition and subtraction, left to right doesn’t matter.

          1 + 2 + 3 = 3 + 2 + 1

          • MotoAsh@piefed.social
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            10 hours ago

            True, but as with many things, something has to be the rule for processing it. For many teachers as I’ve heard, order of appearance is ‘the rule’ when commutative properties apply. … at least until algebra demands simplification, but that’s a different topic.

              • MotoAsh@piefed.social
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                8 hours ago

                No, you completely misunderstood my point. My point is not to describe all valid interpretations of the commutative property, but the one most slow kids will hear.

                OFC the actual rule is the order doesn’t matter, but kids that don’t pick up on the nuance of the commutative property will still remember, “order of appearance is fine”.

        • 0x0@lemmy.zip
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          7 hours ago

          More like a sad realization of the state of (un)education in some parts of the so-called civilized world.
          You laugh not to cry.

        • NewDark@lemmings.world
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          1 day ago

          I think it’s meant to play with your expectations. Normally someone’s take being posted is to show them being confidently stupid, otherwise it isn’t as interesting and doesn’t go viral.However, because we’re primed to view it from that lens, we feel crazy to think we’re doing the math correctly and getting the “wrong answer” from what we assume is the “confident dipshit”.

          There’s layers beyond the superficial.

          • namingthingsiseasy@programming.dev
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            20 hours ago

            I fell for it. It’s crazy to think how heavily I’ve been trained to believe everything I see is wrong in the most embarrassing and laughable way possible. That’s pretty depressing if you think about it.

      • SSUPII@sopuli.xyz
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        1 day ago

        Yeah I know that. But I was feeling confused as to why it was here. That’s why I was feeling trolled, because it made me doubt basic math for being posted in a memes community.

        • JackbyDev@programming.dev
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          15 hours ago

          They did the joke wrong. To do it right you need to use the ÷ symbol. Because people never use that after they learn fractions, people treat things like a + b ÷ c + d as

          a + b
          -----
          c + d
          

          Or (a + b) ÷ (c + d) when they should be treating it as a + (b ÷ c) + d.

          That’s the most common one of these “troll math” tricks. Because notating as

          a + b + d
              -
              c
          

          Is much more common and useful. So people get used to grouping everything around the division operator as if they’re in parentheses.

            • JackbyDev@programming.dev
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              13 hours ago

              Now that’s a good troll math thing because it gets really deep into the weeds of mathematical notation. There isn’t one true order of operations that is objectively correct, and on top of that, that’s hardly the way most people would write that. As in, if you wrote that by hand, you wouldn’t use the / symbol. You’d either use ÷ or a proper fraction.

              It’s a good candidate for nerd sniping.

              Personally, I’d call that 36 as written given the context you’re saying it in, instead of calling it 1. But I’d say it’s ambiguous and you should notate in a way to avoid ambiguities. Especially if you’re in the camp of multiplication like a(b) being different from ab and/or a × b.

            • MotoAsh@piefed.social
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              14 hours ago

              Well, now you might be running into syntax issues instead of PEMDAS issues depending on what they’re confused about. If it’s 12 over 2*6, it’s 1. If it’s 12 ÷ 2 x 6, it’s 36.

              A lot of people try a bunch of funky stuff to represent fractions in text form (like mixing spaces and no spaces) when they should just be treating it like a programmer has to, and use parenthesis if it’s a complex fraction in basic text form.

            • Feathercrown@lemmy.world
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              14 hours ago

              The P in PEMDAS means to solve everything within parentheses first; there is no “distribution” step or rule that says multiplying without a visible operator other than parentheses comes first. So yes, 36 is valid here. It’s mostly because PEMDAS never shows up in the same context as this sort of multiplication or large fractions