Every one of these only makes me say “wouldn’t it be great if we did everything with RPN”?
A fake Facebook event disguised as a math problem has been one of its top posts for 6 months
Submitted 10 months ago by Obelix@feddit.org to technology@lemmy.world
Comments
frezik@midwest.social 10 months ago
NigelFrobisher@aussie.zone 10 months ago
Arguing about maths is like dancing to architecture.
captainlezbian@lemmy.world 10 months ago
Hey, some architecture is asking for it like Stonehenge
Clent@lemmy.dbzer0.com 10 months ago
Anyone on Facebook that attempts to answer this or engage within its comments has already failed the test.
lastunusedusername2@sh.itjust.works 10 months ago
Anyone on Facebook
that attempts to answer this or engage within its commentshas already failed the test.
billwashere@lemmy.world 10 months ago
So order of operations is hard?
SmartmanApps@programming.dev 9 months ago
So order of operations is hard?
Not for students it isn’t. Adults who’ve forgotten the rules on the other hand…
Gsus4@mander.xyz 10 months ago
Next we’re going to have an epic debate on whether work done by the system is positive or negative and we’re all going to feel really smart and passionate about it. Like one of those Science vs Religion debate clubs.
Zenith@lemm.ee 10 months ago
Yeah and I’m tired of pretending it’s not!
HereIAm@lemmy.world 10 months ago
The issue normally with these “trick” questions is the ambiguous nature of that division sign (not so much a problem here) or people not knowing to just go left to right when all operators are of the same priority. A common mistake is to think division is prioritised above multiplication, when it actually has the same priority. Someone should have included some parenthesis in PEDMAS aka. PE(DM)(AS) 😄
SmartmanApps@programming.dev 9 months ago
The issue normally with these “trick” questions
There’s no “trick” - it’s a straight-out test of Maths knowledge.
the ambiguous nature of that division sign
Nothing ambiguous about it. The Term of the left divided by the Term on the right.
A common mistake is to think division is prioritised above multiplication
It’s not a mistake. You can do them in any order you want.
when it actually has the same priority
Which means you can do them in any order
AnotherPenguin@programming.dev 10 months ago
Another common issue is thinking “parentheses go first” and then beginning by solving the operation beside them (mostly multiplication). The point being that what’s inside the parentheses goes first, not what’s beside them.
vithigar@lemmy.ca 10 months ago
The same priority operations can be done in any order without affecting the result, that’s why they can be same priority and don’t need an explicit order.
6 × 4 ÷ 2 × 3 ÷ 9 evaluates the same regardless of order. Can you provide a counter example?
superminerJG@lemmy.world 10 months ago
question: is there something more than the expression evaluating to 11?
DancingBear@midwest.social 10 months ago
[deleted]0xD@infosec.pub 10 months ago
How do you get 5?
Multiplication and division go first, so it’s 9-1+3=11
CaptPretentious@lemmy.world 10 months ago
This thread shows that a whole bunch of people need to start taking online education courses. Getting back your algebra skills, some science perhaps, communication, history, etc.
I don’t know where you can get a proper education for that after grade school, but I see Brilliant.org advertised a lot.
Dreaming_Novaling@lemmy.zip 10 months ago
I was good at math and it was one of my favorite core subjects in school, so I know I’m a weirdo but… I never understood how people couldn’t understand basic PEMDAS/BEDMAS/Whatever-the-fuck-your-country-calls-it.
Obviously these problems are shitty engagement bait because they don’t use parentheses, but still, seeing people fuck up the fact that Multiplication AND Division occur at the same time, and then the next step is Addition AND Subtraction just stupefies me.
Like, did you sleep through 4 years of elementary school to miss that fact??? Even in middle school pre-algebra teachers still did PEMDAS refreshers. I get that once I get out of college I’m probably gonna forget half the pre-calc shit I learned because I won’t need it, and I’m not being drilled on it everyday like people in school are, but PEMDAS is a fundamental and basic daily life skill that everyone should know…
I really wish we gave a fuck about US education.
barsoap@lemm.ee 10 months ago
I never understood how people couldn’t understand basic PEMDAS/BEDMAS/Whatever-the-fuck-your-country-calls-it.
There’s no “whatever-the-fuck-your-country-calls-it”, the US is the only country using it, and only up to high school. At least I’m not seeing any papers coming out of the US relying on it so at some point they’re dropping it and do what everyone else is doing: Write equations such that you don’t need a left-to-right rule to disambiguate things. Also, using multiplication by juxtaposition (2a + 4a^2^).
SmartmanApps@programming.dev 9 months ago
There’s no “whatever-the-fuck-your-country-calls-it”
Yes there is. BEDMAS, BODMAS, and BIDMAS
the US is the only country using it
No they’re not.
at some point they’re dropping it
No, at no point do the order of operations rules ever get dropped
using multiplication by juxtaposition (2x + 4x2)
They’re called Terms/Products.
AlphaOmega@lemmy.world 10 months ago
I was bad at math, but I still managed to get through precal and still remember PEMDAS
kameecoding@lemmy.world 10 months ago
For me it’s the arguments when there is a parentheses but no operator in these baits e.g. 2(4 - 2)
If you don’t know operator orders I have given up long ago, but I have seen a few lengthy discussions about this
SmartmanApps@programming.dev 9 months ago
For me it’s the arguments when there is a parentheses but no operator (otherwise known as implied multiplication)
No, it’s known as Factorised Terms/Products, solved via The Distributive Law, a(b+c)=(ab+ac). “implied multiplication” is a made up rule by people who have forgotten the actual rules, and often they get it wrong (because, having wrongly called it “multiplication”, they then wrongly give it the precedence of multiplication, not brackets).
Mistic@lemmy.world 10 months ago
Oh yeah, that’s a fun one.
Where I live, this would be considered juxtaposition, at least by uni professors and scientific community, so 2(4-2) isn’t the same as 2×(4-2).
This way, equations such as 15/2(4-2) end up with a definite solution.
Usually, however, it is obvious even without assuming juxtaposition because you can look at previous operations. Not to mention that it’s most common with variables (Eg. “2x/3y”).
So,
15/2(4-2) = 3.75
While
15/2×(4-2) = 15
roofuskit@lemmy.world 10 months ago
This is the kind of post designed to invoke a reaction. Facebook’s and pretty much every other algorithm driven social media is designed to promote posts that have high interaction. So a post that invokes lots of negative reactions gets lots of promotion. Hence the downfall of modern society.
jjjalljs@ttrpg.network 10 months ago
This kind of problem falls under “communicating badly and acting smug when misunderstood”. Use parenthesis and the problem goes away.
SmartmanApps@programming.dev 9 months ago
This kind of problem falls under “communicating badly and acting smug when misunderstood”.
No it doesn’t. It falls under adults forgetting the rules of Maths.
themagzuz@lemmy.blahaj.zone 10 months ago
on that note, can we please have parentheses in language. i keep making ambiguous sentences
Gsus4@mander.xyz 10 months ago
My language teachers always told me it was bad form to use too much or even to nest parenthesis…
Then I found lisp…
gamer@lemm.ee 10 months ago
This is why grammar is important, and “grammar nazis” are the only good kind of nazis.
barsoap@lemm.ee 10 months ago
Clent@lemmy.dbzer0.com 10 months ago
People try and use commas for this sort of clarification and are eviscerate for it.
With these sort of math problems, the rules are taught early and then all subsequent math is written in an unambiguous form.
Language has the oddity of going the other way around where the rules get more complex as a display for advanced skilled.
AbidanYre@lemmy.world 10 months ago
Isn’t that basically what commas are for?
KingPorkChop@lemmy.ca 10 months ago
Why (I don’t see) not
entropicdrift@lemmy.sdf.org 10 months ago
We have them in written language, though?
manuc66@programming.dev 10 months ago
÷ could be a minus sign see en.wikipedia.org/wiki/Division_sign?wprov=sfla1
SmartmanApps@programming.dev 9 months ago
÷ could be a minus sign
No it couldn’t.
Did you check the reference? It says % can be used as a minus sign, not the obelus. Welcome to what happens when you’re next-door neighbour Joe Blow can edit Wikipedia.
manuc66@programming.dev 8 months ago
Yes I did, on page 243:
It was employed in the Philosophical Transactions by the Dutch astronomer N. Cruquius; ÷ is found in Hübsch and Crusius. It was used very frequently as the symbol for subtraction and ``minus´´ in the Maandelykse Mathematische Liefbebbery, Purmerende (1754-69)
Venator@lemmy.nz 10 months ago
Except that it has English text above it…
nuko147@lemm.ee 10 months ago
Boomers and Xgens need to prove, that they remember basic school math in FB lmao.
corsicanguppy@lemmy.ca 10 months ago
I’m more worried about the gratuitous comma and what it means for the state of education.
nuko147@lemm.ee 10 months ago
Nah, people can write things while being a bit drunk, you know. I’m speaking for a friend, not me, ofc.
thedruid@lemmy.world 10 months ago
Gen xers? Don’t like them. They’re not noticing you right now.
Very independent, and cranky generation.
systemglitch@lemmy.world 10 months ago
Who, the people who never had calculators in their pockets? No worries, we can do math better than you.
wondrous_strange@lemmy.world 10 months ago
Knowing basic arithmetic does not mean you know Math, and the fact you so hung up about this trivial aspect says a lot about you. Additionally, you express yourself like a boomer.
jordanlund@lemmy.world 10 months ago
I’m sure we’re all geniuses here, but just in case…
Please excuse my dear aunt Sally.
Parenthesis, exponents, multiplication, division, addition, subtraction.
Why? Becauseca bunch of dead Greeks say so!
3x3-3÷3+3
(3x3)-(3÷3)+3
9-1+3
8+3
11
Mistic@lemmy.world 10 months ago
The “why” goes a little further than that.
In actuality, it’s because of fundamental properties of operations
- Commutation
a + b = b + a
a×b = b×a
- Association
(a + b) + c = a + (b + c)
(a×b)×c = a×(b×c)
- Identity
a + 0 = a
a×1 = a
If you know that, then PEMDAS and such are useless because they’re derived from those properties but do not fully encompass them.
Imgonnatrythis@sh.itjust.works 10 months ago
Not a genius. But if subtraction is last, why isn’t it 9-4?
cecilkorik@lemmy.ca 10 months ago
Parenthesis, exponents, multiplication, division, addition, subtraction.
should actually be
Parenthesis, exponents, (multiplication and division), (addition and subtraction).
Addition and subtraction are given the same priority, and are done in the same step, from left to right.
It’s not a great system of notation, it could be made far clearer (and parenthesis allow you to make it as clear as you like), but it’s essentially the universal standard now and it’s what we’re stuck with.
Geodad@lemm.ee 10 months ago
It’s multiplication or division from left to right followed by addition or subtraction, also from left to right.
That’s where a lot of people fuck up.
fluxion@lemmy.world 10 months ago
Addition/subtraction work out the dame regardless of how you order the operations. If you do subtraction last you have:
9-1+3
and you are adding 3 to the result of (9-1). Since you are trying to perform it before the (9-1) operation is carried out, you can add 3 to the 9:
12-1 = 11
or you can add three to the -1 and get:
9+2 = 11
You only end up with 9-4 if you were subtracting 3 rather than adding three. It all becomes more obvious if you read the original as:
9 + (-1) + 3
aliceblossom@lemmy.world 10 months ago
Because its not really “1 plus 3”, its negative 1 plus 3 which is two. I know it seems a little weird but the minus sign is " tied" to the thing following it.
barsoap@lemm.ee 10 months ago
Why? Because a bunch of dead Greeks say so!
The Greeks certainly didn’t come up with PEMDAS. US teachers too lazy to teach kids actual maths did. And that’s before taking into account that the Greeks didn’t come up with Algebra.
dohpaz42@lemmy.world 10 months ago
US teachers too lazy to teach kids actual maths did.
What’s lazy about learning PEMDAS? And what’s the non-lazy/superior way?
pulsewidth@lemmy.world 10 months ago
[deleted]jordanlund@lemmy.world 10 months ago
Multiplication and Division, and Addition and Subtraction are executed at the same level and done in left to right order.
czardestructo@lemmy.world 10 months ago
I guess remembering grade school order of operation means you’re a guinus now? Bar has gotten pretty low…
rigatti@lemmy.world 10 months ago
G U I N U S.
I know it’s probably a typo, but I’m enjoying it.
SARGE@startrek.website 10 months ago
That’s the point.
Set the bar low, but just high enough that tons of people still trip over it.
Sit back and enjoy the comment wars.
The people who are confident but wrong are too proud to admit they were wrong even if they realize it, and comment angrily.
The people who are right and know why, comment for corrections and some to show off how S-M-R-T they are.
The people who are wrong but willing to accept that just have their realization and probably don’t think about it again. So do the people who don’t know and/or care.
But those first two groups will keep the post going in both shares and comments, because “look at all these wrong people”
It’s all designed to boost engagement.
AnotherPenguin@programming.dev 10 months ago
And it will go even lower as people start relying mpre on AI…
vext01@lemmy.sdf.org 10 months ago
For the programmers: operator precedence.
queermunist@lemmy.ml 10 months ago
So if it’s not really an event
And it’s not really a math problem
What the hell is it??
catloaf@lemm.ee 10 months ago
Engagement bait
Zwuzelmaus@feddit.org 10 months ago
Entertainment.
The only thing that will remain on yt anyway after AI has taken over the content generation and we can trust no “creator” anymore.
aMockTie@lemmy.world 10 months ago
Hey, this is Presh Talwalkar.
discussion of a brief history of this viral math problem, followed by explanations of common incorrect answers. Finally followed by brief discussion on the order of operations, concluding in a final example that ultimately equals 11
And that’s the answer. Thank you so much for making us one of the best communities on YouTube, where we solve the world’s problems, one video at at time.
SmartmanApps@programming.dev 9 months ago
Hey, this is Presh Talwalkar
Person who has forgotten about The Distributive Law and lied about 1917.
Discussion of a brief history of this viral math problem
Including lying about 1917
Ultimately followed by brief discussion on the order of operations
But forgets about Terms and The Distributive Law.
And that’s the answer
Now watch his other ones, where he screws it up royally. Dude has no idea how to handle brackets. Should be avoided at all costs.
aMockTie@lemmy.world 9 months ago
I’ve seen many of his videos and haven’t noticed any obvious errors. Could you please link to the specific video(s) that you are referencing in regards to errors he has made, especially those related to the distributive law and what your reference to “1917,” as well as any explanation as to what is incorrect/misleading/lying?
maniacalmanicmania@aussie.zone 10 months ago
What’s the scam?
drool@lemmy.catsp.it 10 months ago
11
Lembot_0002@lemm.ee 10 months ago
Yes, we can count. I suppose the question was “So what? What is scummy in some viral post?”
cabbage@piefed.social 10 months ago
Not strictly a scam, but there's a little money to be made creating viral content on Facebook. They receive a tiny portion of the ad revenue from Facebook when they generate engagement.
It's just Facebook sucking really.
maniacalmanicmania@aussie.zone 10 months ago
Thanks 🙏
Almacca@aussie.zone 10 months ago
Ah, yes. It’s only for genius.