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 :)
.
?
!
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Ackshually, the answer is 4
6÷2*(1+2)
6÷(1+2)*2
6÷(3)*2
2*2
4
You're welcome
If there are rules about which dot comes first then you are not allowed to do this.
You guys are doing it all wrong: ask chatgpt for the correct answer and paste it here. Done.
Who needs to learn or know anything really?
If you are so sure that you are right and already “know it all”, why bother and even read this? There is no comment section to argue.
I beg to differ. You utter fool! You created a comment section yourself on lemmy and you are clearly wrong about everything!
You take the mean of 1 and 9 which is 4.5!
/j
🤣 I wasn't even sure if I should post it on lemmy. I mainly wrote it so I can post it under other peoples posts that actually are intended to artificially create drama to hopefully show enough people what the actual problems are with those puzzles.
But I probably am a fool and this is not going anywhere because most people won't read a 30min article about those math problems :-)
I did (skimmed it, at least) and I liked it. 🙃
Actually the correct answer is clearly 0.2609 if you follow the order of operations correctly:
6/2(1+2)
= 6/23
= 0.26
🤣 I'm not sure if you read the post but I also wrote about that (the paragraph right before "What about the real world?")
I did read the post (well done btw), but I guess I must have missed that. And here I thought I was a comedic genius
Right, because 5 rounds down to 4.5
Not sure if sarcastic and woosh, or adding to the joke ಠ_ಠ
The mean of 1 and 9 is 5
woosh
It's not ambiguous, it's just that correctly parsing the expression requires more precise application of the order of operations than is typical. It's unclear, sure. Implicit multiplication having higher precedence is intuitive, sure, but not part of the standard as-written order of operations.
I'd really like to know if and how your view on that matter would change once you read the full post. I know it's very long and a lot of people won't read it because they "already know" the answer but I'm pretty sure it would shift your perception at least a bit if you find the time to read it.
My opinion hasn't changed. The standard order of operations is as well defined as a notational convention can be. It's not necessarily followed strictly in practice, but it's easier to view such examples as normal deviation from the rules instead of an implicit disagreement about the rules themselves. For example, I know how to "properly" capitalize my sentences too, and I intentionally do it "wrong" all the time. To an outsider claiming my capitalization is incorrect, I don't say "I am using a different standard," I just say "Yes, I know, I don't care." This is simpler because it accepts the common knowledge of the "normal" rules and communicates a specific intent to deviate. The alternative is to try to invent a new set of ad hoc rules that justify my side, and explain why these rules are equally valid to the ones we both know and understand.
The difference is that there are two sets of rules already in use by large groups of people, so which do you consider correct?
I guess if you wrote it out with a different annotation it would be
-‐--------‐--------------
=
-‐--------‐--------------
=
--‐--------‐--------------
=1
I hate the stupid things though
Markdown fucked your comment. Use escape symbols.
Escape symbols?
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Hi, I’m stupid, is it 1+2 first, then multiple it by 2, then divide 6 by 6?
Or is it 1+2, then divide 6 by 2, then multiple?
I think it’s the first one but I’ve got no idea.
It's actually "both". There are two conventions. One is a bit more popular in science and engineering and the other one in the general population. It's actually even more complicated than that (thus the long blog post) but the most correct answer would be to point out that the implicit multiplication after the division is ambiguous. So it's not really "solvable" in that form without context.
You’d think we would’ve solve this with Einstein or Aristotle or something.
It's not a math problem, it's a communication problem. The person who wrote it down didn't make themselves clear
Build two cases, calculate for both, drag both case through the entirety of both problems, get two answers, make a case for both answers, end up with two hypothesis. Easy!
Having read your article, I contend it should be:
P(arentheses)
E(xponents)
M(ultiplication)D(ivision)
A(ddition)S(ubtraction)
and strong juxtaposition should be thrown out the window.
Why? Well, to be clear, I would prefer one of them die so we can get past this argument that pops up every few years so weak or strong doesn't matter much to me, and I think weak juxtaposition is more easily taught and more easily supported by PEMDAS. I'm not saying it receives direct support, but rather the lack of instruction has us fall back on what we know as an overarching rule (multiplication and division are equal). Strong juxtaposition has an additional ruling to PEMDAS that specifies this specific case, whereas weak juxtaposition doesn't need an additional ruling (and I would argue anyone who says otherwise isn't logically extrapolating from the PEMDAS ruleset). I don't think the sides are as equal as people pose.
To note, yes, PEMDAS is a teaching tool and yes there are obviously other ways of thinking of math. But do those matter? The mathematical system we currently use will work for any usecase it does currently regardless of the juxtaposition we pick, brackets/parentheses (as well as better ordering of operations when writing them down) can pick up any slack. Weak juxtaposition provides better benefits because it has less rules (and is thusly simpler).
But again, I really don't care. Just let one die. Kill it, if you have to.
I think anything after (whichever grade your country introduces fractions in) should exclusively use fractions or multiplication with fractions to express division in order to disambiguate. A division symbol should never be used after fractions are introduced.
This way, it doesn't really matter which juxtaposition you prefer, because it will never be ambiguous.
Anything before (whichever grade introduces fractions) should simply overuse brackets.
This comment was written in a couple of seconds, so if I missed something obvious, feel free to obliterate me.
Just write it better.
6/(2(1+2))
Or
(6/2)(1+2)
That's how it works in the real world when you're using real numbers to calculate actual things anyways.
But how would that go viral?
This is not a math problem but a calculator engineering problem. Some solve the sub operations from right to left while other do it from left to right.