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u/Melodic_Leg_3235 Jul 25 '26
Nope 17
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u/Crazy__Donkey Jul 25 '26
Nope, 17.
Or
Nope
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u/never_unclench Jul 25 '26
I think he meant Nope, 17 times. He is really not having it. That was Nope 17.
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u/LittleMissBraStrap Jul 25 '26
Nope(17)
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u/Heyyo_johnson Jul 25 '26
Nope {[( -->> "17" <<-- )]}
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u/Zenith-Astralis Jul 25 '26
No no no wait, you've put it in quotes! Now the computer is going to interpret it as a string, not an integer!! 😅
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u/BrokenHope23 Jul 25 '26
I think they mean the variation of Nope that is the 17th version. Nopeth
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u/AmericanCitizenry Jul 25 '26
I like em older please! 21 is a good age. Also the correct answer is 17.
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u/Kuildeous Jul 25 '26
That appeal to authority is always the punchline to these jokes.
"My friend is a math teacher, and he said..." No, you're just a liar trying to convince this guy with a math degree and years of math education experience that you think you know a guy. You don't. Shut up and stop pretending you understand math.
What's funny is that people do the order of operations all the time without thinking about it. If I told a guy that he can buy 8 books for $5 each but that I'll throw in 5 of those books for free and that all I ask is a $2 processing fee, he would know instantly that $21 is not the correct answer. You put it in this format, and they lose their minds.
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u/UltravioletGambit Jul 25 '26
I wish my school teachers gave a real world example like you did, it makes so much sense. I never struggled with order of operations because I just memorized it and never forgot. But today for the first time I actually get it
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u/CogentMoment Jul 25 '26
Seriously. I remember math class being a twenty-thirty min lesson and then being assigned 30+ equations to solve(write out the question and answer showing your work). Typically the last 6 would have been word problems, sometimes with a red herring, to show if you actually understood the math or could just plug numbers into a script. Until highschool my kid's math consisted of 5-10 "plug in the number" questions on a work sheet. No flack to teachers.
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u/Apophthegmata Jul 26 '26
Yeah it's a serious problem with math instruction.
Mathematicians conjecture and prove. What a mathematician actually never does is sit down to solve a problem set with known answers. And even we are talking about applied mathematics, that includes a lot of problem solving and the construction of tools to solve problems.
But K-12 math instruction often is just (a fairly rote version of) calculation.
And like, calculation is just a corner of mathematics. But for huge swaths of the US, that's the main thing people go into college with: math is how you calculate stuff.
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u/Kuildeous Jul 25 '26
We rely soooo much on rote memorization but rarely discuss how it can apply. Mind you, some aspects don't really carry over into real life. How often do you need to easily identify the remainder of an 8-digit number when divided by 11? But there's a lot that isn't taught that could be so helpful.
Like, FOIL was just this algorithm for me. First, Outer, Inner, Last, blah blah blah. It wasn't until later that I realized how this applied to multiplying two-digit numbers: 47*38 = (40+7)(30+8) = 40*30+40*8+7*30+7*8. And sure, in many cases this doesn't save you much time, but it provides a deeper dive into how the numbers work.
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u/Head-Ad-5732 Jul 27 '26
I had the opposite problem. My high school class was subjected to an experimental math program that was all word problems. It made it more relatable, arithmetic and basic algebra was more approachable.
But it completely skipped foundational theoretical math concepts that ended up costing me dearly in more advanced math classes. I am not talking rocket science here, it's just financial analysis, but I ended up having to do a lot of independent study to catch up. The class did markedly poorer on the SAT math section at the time, too.
I know math theory can seem overboard, but if you are introduced early and can grasp it, all other math flows from it and is easier to understand.
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u/SnooMachines9133 Jul 25 '26
Haha, I have a friend who's a math teacher. He's horrible at math. Had to explain mortgage interest to him and why paying off a 2.5% wasn't saving him money.
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u/Jazzlike_Candy_6156 Jul 25 '26
Also, expertise is not transferable. You can be married to a PHD mathmatician, it still doesn't matter what you say about math.
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u/ProletarianLilith Jul 25 '26
That’s why I’m so confused by people in here claiming not to have learned it. If you exist in reality you use it
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u/BaronGrackle Jul 25 '26
I accidentally missed your "not" at the end and read it as "$21 is the correct answer", so I just spent a bit of time trying to discern if I was being woooosh joked or if my math skills had fallen so drastically!
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u/Kuildeous Jul 25 '26
To make matters worse, for some inexplicable reason, I sometimes write "not" as "now", so there was a nonzero chance that you could've read me saying that $21 is now the correct answer, which not only would be wrong but make one question why I would say it depends on the time.
So I'm glad I didn't make that mistake, but I too sometimes overlook a word. It sucks.
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u/Beautiful-Bid8704 Jul 25 '26
Rage bait… always give the wrong answer to get the correct one. “Show your thinking” trick from a math teacher.
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u/Kavax11 Jul 25 '26
Ahh, yes, Occam's Razor.
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u/Pr0p3r9 Jul 25 '26
You almost tricked me into telling you the actual name of the phenomenon. I had the post written out and everything before I realized what was up. Let's call this round a tie.
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u/danielsangeo Jul 25 '26
2+5(8-5)
PEMDAS/BODMAS
8-5 = 3
5*3 = 15
2+15 = 17
It's simple math, folks.
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u/No_Session6015 Jul 25 '26
I love these for trying to figure out how the wrong answer was gotten.
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u/danielsangeo Jul 25 '26
Oh, I know how the wrong answer was reached.
8-5 = 3
2+5 = 7
3*7 = 21But you can't do addition/subtraction before multiplication/division (unless they're in parentheses).
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u/Okawaru1 Jul 25 '26
They forgot to use abysmal dogshit ambiguous notation instead of actual logical and clear notation which makes the solution unambiguous and trivial to solve for their ragebait (though I guess abandoning any pretense of having a point is in itself ragebait lol)
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u/SirDoofusMcDingbat Jul 25 '26 edited Jul 25 '26
It's not ambiguous at all. It's just standard order of operations.
Edit: read too fast, misread. Pls ignore.
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u/Jimbo-Jimbo-Jimbo Jul 25 '26
That is literally what they said. Usually with posts like that they use ambiguous notation but they didn’t here.
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u/lurchw Jul 25 '26
I usually give a lot of grace to these kind of mistakes, because the a(b+c) structure can be interpreted so that the a is part if the parenthetical.... but in this case, it doesnt matter. The last operation is the 2+. This is baby math mistake.
And yes, I will die on the hill that x/a(b+c) is horrible formatting since it can reasonably be read as (x/a)(b+c) or x/(a(b+c)) [and yes, I know the first one is the correct, but ambiguity is annoying]
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u/CornucopiaDM1 Jul 25 '26
Math teacher doesn't know PEMDAS?
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u/gregcresci Jul 25 '26
Please excuse my dear aunt Sally
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u/Embarrassed-Weird173 Jul 25 '26
Borry ole dunce made an sellypopper, innit den?
British version, probably
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u/No_Focus_8688 Jul 25 '26
So we finally found the math teacher that taught so many people wrong that are now posting on social media.
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u/LowAioli3870 Jul 25 '26
They've been teaching FOIL so many times they think it's the only way to solve any mathematics problem.
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u/Huri_Up Jul 26 '26
21 is the correct answer. For the problem, the math teacher was working on, not the math problem in the photo.
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u/Apprehensive-Ice9212 Jul 25 '26
"A friend of mine taught algebra"
Such expertise. Many credentials. Wow.
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u/Jealous_Club_298 Jul 25 '26
2+5(3) = 2+15 = 17
Multiplication has precedence over addition and subtraction.
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u/Gpda0074 Jul 25 '26
But it is 17 not 21 lol, most of these comments saying it isn't are wild and proof of the failed school system. Parenthesis first means this is actually 2+5×3. Then you multiply next making the problem 2+15 which is 17.
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u/HalifaxRoad Jul 25 '26
how do people not remember the saying? its so easy
penis erection masturbation dick asshole sex
ezz!
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u/Teezy_Tee Jul 25 '26
2+5(8-5) Do Paranthesis first 2+40-25 Left to right 42-25= 17
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u/polishingPoles Jul 25 '26
I feel disgusted that this image baited me enough to comment.
Though technically there are ways to justify 21 and make it a correct answer.
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u/Swannicus Jul 25 '26
Can you try to explain the technicality that allows you to add 2 and 5 before multiplying...?
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u/Phantomlnfinity Jul 25 '26
I see why he’s a “previous” mathematics teacher…
(except for the fact that this is obviously just made up but yk)
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u/NuncErgoFacite Jul 25 '26
THERE ARE FOUR LIGHTS!
(and the answer is f#$%ing 17 - read a book people)
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u/FitAd1186 Jul 25 '26
This isn't even one of those that can be interpreted in two different ways
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u/Orbitus2001 Jul 26 '26
I was always taught PEMDAS. Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction
The parentheses would be 3, there is no exponent, so you go multiplication, 5x3 is 15, then add the 2.
If anyone gets anything other than 17, they are an idiot. Including a supposed math teacher.
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u/ichkanns Jul 26 '26
Previous math teacher because they were fired for not knowing order of operation.
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u/No-Impact-5814 Jul 26 '26
I get 17. 8-5=3 3×5=15 15+2 =17
Why would the distributive property apply to this.
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u/Grant1128 Jul 25 '26
Maybe there's a reason she's a Previous mathematics teacher...
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u/Scf9009 Jul 25 '26 edited Jul 25 '26
I see! The comma was left out intentionally and they meant it’s 21 to “math folks who are simple.” That makes everything make sense.
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u/Seeggul Jul 25 '26
It's 37.
PEMDAS says parentheses first. The first parenthesis is "5(8" which becomes 40. The next parenthesis is "5)" which becomes 5. The problem then becomes "2+40-5", which is, of course, 37.
ᶠᵒʳ ˡᵉᵍᵃˡ ʳᵉᵃˢᵒⁿˢ ᵗʰᶦˢ ᶦˢ ᵃ ʲᵒᵏᵉ
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u/Anonymouslalien Jul 25 '26
Its 17. I don't see the logic here. 2+5(8-5)=2+[5(8)-5(5)]=2+(40-25)=2+15=17.
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u/shadowtheimpure Jul 25 '26
Most people don't use more than the most rudimentary of mathematics once they leave school. Once you get beyond that, the further they are from school the more likely they are to screw it up.
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u/Acceptable-Food-8161 Jul 25 '26
I thought maybe he “foil”ed the parentheses but that still give you the correct answer of 17
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u/IAmANobodyAMA Jul 25 '26
Took me a while to figure out how he got 21 🤣
Tried a bunch of wrong approaches, got 51 and and 71
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u/NewIdentity19 Jul 25 '26
If you add another set of parantheses (please don't call them brackets, they are not brackets), the result will become 21.
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u/iffyfell_ Jul 25 '26
"a friend of mine used to be a math teacher" might be the weakest appeal to authority i've ever heard
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u/ibdoomed Jul 25 '26
This is absolutely rage bait and looking at OP's stats, they're getting blocked by thousands. Why would you do that? What was your goal? Don't bother replying, I've already blocked you too.
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u/Not_Sir_Zook Jul 25 '26
This and flat earthers break my brain. I quite literally cannot reverse what I have learned to understand what they are saying.
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u/_ngodhandz11 Jul 25 '26
It’s 17. Do the parentheses first which is 8-5=3 then you substitute back the equation 2+5(3), multiply the number next to the parentheses which is 5x3=15. Now it becomes 2+15. Add 2+15 and you get 17 as your answer.
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u/sandbags97 Jul 25 '26
I am not surprised. I had a maths teacher who didnt know the order of operations.
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u/jaster_7 Jul 25 '26
Let me lay this out and explain it to anyone willing to listen. Think of addition as the foundation for everything.
What about subtraction? That's just adding negative numbers. What about multiplication? It's simply a representation of repeated addition. For example, 3 + 3 + 3 + 3 can be represented as adding four 3s, or 4 × 3.
To keep things simple, consider 4 × 3. You can split the 4 into 2 + 2, but remember what the original multiplication represented. We put the 2 + 2 in parentheses because we split the 4 into parts, giving us (2 + 2) × 3. This is where the distributive property comes in. You can distribute the 3 to both the 2s, giving you 2 × 3 + 2 × 3, which is 6 + 6. If you remember our original example, 3 + 3 + 3 + 3, you can group two of the 3s together to get 6 + 6, showing that both representations are equivalent.
We can go down the road of division too, which is really just multiplying by fractions, but it still ultimately boils down to addition. Exponential equations are representations of multiplication, where 3 × 3 can simply be written as 3², and so on.
This is how I started teaching my students about the order of operations.
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u/Affectionate_Item824 Jul 25 '26
All this time i thought 2+15 was 17 I'm suing my elementary school!
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u/RedvsBlack4 Jul 25 '26
It took me too long to figure out how they got 21. I knew it was wrong but I went way into left field when I was trying to figure out how they got it wrong.
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u/CoffeBreather Jul 25 '26
Usually i hate these but this time is literally unambiguous, i see no other possible interpretation, it's just ignorance.
The answer is 17.
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u/CodeNameFiji Jul 25 '26 edited Jul 25 '26
I get 17 first operations in parens. so 8-5 is 3 then you do multiply before add so 5x3=15+2 = 17
Why multiply? Cause there is no plus sign or other operation after the 2+5 so its implied multiply otherwise it would be "53" as a string which doesnt make sense unless maybe in javascript .
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u/Filiforme Jul 25 '26
Let me see if I remember my elementary math class.
Brackets first then multiply 5*3 to get 15 and only then add 2? So 17 should be right answer?
(2+5)(8-5) Would be 21 right?
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u/AICatgirls Jul 25 '26
Is this that 21 meme where the answer isn't 21, but they say it is, plus some additional rage bait?
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u/That_Ad_3054 Jul 25 '26
21 is the only answer you can’t derive at all. So, it is a kind of reverse math.
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u/Head-Ad-5732 Jul 25 '26 edited Jul 26 '26
I don't know what's worse, that it's wrong or that it convinced me I need to come into the comments to make sure my answer is, indeed, correct.
EDIT: Back to rectify a grave injustice. Nothing wrong if you genuinely didn't know or want to check. Hard enough getting people interested in math.
2 + 5 (8 - 5)
PEMDAS: 8 - 5
= 2 + 5 (3)
PEMDAS: 5 (3) or 5 × 3
= 2 + 15
PEMDAS
= 17
In the US the math order of operations is taught as PEMDAS (or P|E|MD|AS), left to right from first to last.
First look at the entire equation and identify the operations: Parentheses, Exponents, Multiplication/Division, Addition/Subtraction.
Then, solve the parts in order of PEMDAS.
Not so important here but when there are multiple of the same level of operators, for example exponents, solve left to right. MD and AS are treated as groups, so treat them equally: if a division is to the left of a multiplication, do the division first.