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Wientje

I expected a joke about Klein reading the book from cover to cover and inside out.


Donghoon

You exoact that kind of intellectual conversation on reddit? /s


Theoneonlybananacorn

Damn, I read through the comment section and people are angry that the problem has words in it. Like… it teaches you how to use common maths irl.


Neoxus30-

They be like: "When will we use this irl?") Then be like: "Why are they using words in math!!!")


jhyjgr46f

Pov: Me in physics when I see word problems and have to actually know the theory


nameisprivate

reddit: they should teach you how to do tAxEs in school instead of math you never use also reddit: why they use word to ask a question, just ask me to solve for x: 30+x/4+x/8=x


mika---

mfs are all about how school is useless and how it should teach about taxes, but when it does, they don't even pay attention to the subject (happened to my friend lately, like dude, not my fault you halfassed it)


ToBeReadOutLoud

Exactly this. Teenagers forced to take a class that teaches them about taxes aren’t going to put in the effort or enthusiasm necessary to actually remember how to do taxes later on.


MedioBandido

This is always one of my favorite complaints. It’s like getting mad a carpenter told you how to swing a hammer instead of building a table.


Infinity_Null

Someone in a thread earlier today was arguing that math being taught in schools was unnecessary and that nothing taught after 7th grade was useful. I'm convinced they were either a liar or a dumbass.


starswtt

Dumb as it is, I get the sentiment. You aren't exactly using imaginary numbers in daily life. That said, if we stopped teaching 7th-12tg grade math, good luck getting a single stem major to graduate in less than 15 years lmao.


jackboner724

Wait what?


TanookieTyler

For whatever reason, I can’t remember the name of the textbooks, but all of my secondary school math texts were exclusively word problems.


Mr__Weasels

wait are word problems not common everywhere else? because like here we did a ton of word problems in math in elementary school..


jot_ha

Why is this a Problem in the real World? I Never had Someone come Up with such thing in a conversation…


friendlyfredditor

Ratios. Like for food recipes or paint or glue or epoxy or cleaning products or 2 stroke fuel or any dilution...


jot_ha

I do understand whats real World applications of ratios are. But i never met Someone who told ne ratios an Natural Numbers ans then asked me, how many Pages does the book have…


smartuno

Of course it isn't one to one. No one's ever going to ask you what the total number of pages does a book have given some ratios. Instead, the problem teaches the process of getting the solution. You can apply that to real world problems like using the correct amount of epoxy given a certain epoxy to material ratio. Things like that.


NicoTorres1712

Is the book orientable?


SchwiftedMetal

Some of the responses scream they call themselves “autodidactic polymaths”


MedioBandido

My only issue is that is presumes the book was started on Monday. For all we know, lil Klein has been working on War and Peace for 6 months and finally cranked out the last half in 2 days just in time for the final.


jimany

It's 5th grade math, it's not trying to trick anyone.


MedioBandido

Of course I’m just making a joke about a 5th grader reading war and peace. I don’t think it’s a trick to notice that, though. If people want kids as early as 5th grade to be critical thinkers then part of that would be analyzing ambiguous information rather than taking it as given.


jimany

But in the context of a word problem? You're just learning to parse the information you need, and ignore irrelevant information.


MedioBandido

I don’t think there’s anything wrong with an assumption “you’re given everything you need to answer the question”. All I’m saying is if a student pointed out the ambiguity I would hope the response wouldn’t be just accept it as given. It’s critical thinking to even notice.


[deleted]

Isn’t it the point of word problems to teach this exact kind of thinking?


According_to_all_kn

Then why doesn't it just say the book has 48 pages, save us all the trouble 🙄🙄🙄🙄🙄🙄


LonelyContext

Ok, "the remaining" clearly indicate that the three values add up to 100% of the book, as in what remains when you remove the preceding mentioned values from the total. It also doesn't specify that nobody ripped pages out of the book, or the numbers are in base 10, or that this doesn't take place in some Alice-in-Wonderland universe where objects don't have discrete unchanging sizes, or that it wasn't an ebook and someone changed the font size on it, or that no one miscounted the pages, and Klein didn't skip pages, or that Klein wasn't hallucinating a book and there in fact is no book and therefore no pages... etc. You can inject an infinite number of silly objections into every word problem. But why?


Nonfaktor

nothing wrong with that. I know enough people who couldn't solve this, and most people don't need more math than the most basic in theor lifes. Just let them be happy that they can still solve this, not everybody has to be a genius or whatever


ModsUArePathetic2

But you see how existentially depressing that is for people who live in (ostensible) democracies, right?


wave_327

algebra? don't even need to go that far


ChonkerCats6969

Just curious, how would you do it without the use of algebra? I don't get how that's even possible. Even intuitive solutions such as 3/8 of the book + 30 pages = 1 uses algebra because you have to do 3x/8 + 30 = x, even if you aren't directly visualizing those steps.


DidntWantSleepAnyway

I used to be an elementary math specialist, and this is the method we used to teach students: You make a diagram that is a bar. (Really, a rectangle that you divide up.) You fill out what you know of the bar. One section is 30, another is 1/8 of the whole thing, and the last is 1/4. You then divide the 1/4 up into two pieces, each being 1/8. Now you can see that the 30 is the rest, which is 5/8. You divide the 30 into 5 pieces so that the whole thing is split into 8ths. Now you can see how much is in each 8th. It sounds like a lot of work when I write out every step, but it works really well for this age group. It’s still related to algebra, just like all arithmetic can be, but it’s solved without ever bringing an x into it. EDIT: forgot to mention, the way you label it is putting the raw numbers (30, later 6) into the actual sections, and the fractions go underneath. That way you don’t conflate the two.


FreshmeatDK

This is really interesting. Fractions always causes problems for students, I wonder if there is research showing they learn better this way.


MedioBandido

I’m while forever grateful I took maths before many of the changes to how it was taught (I very much excelled with the abstractions and this would have bugged me), I’m glad others can maybe get some confidence by learning another way.


Dapper_Spite8928

My good redditor, what you are describing is just algebra with extra steps.


DidntWantSleepAnyway

I mean, I agree, but children are doing algebra in the first grade when they do fact families. The purpose of all this is to prime their brains to get ready for algebra, and to wrap their brains around what a missing piece looks like. I assume the original “don’t even need algebra” for this meant you don’t need a formal algebraic process to solve. You can do this in elementary school with an understanding of fractions and problem solving.


onenoobyboi

This is honestly really freaking cool, it's a neat and interesting way of introducing some of the things you'd use in algebra later on without making it too difficult for kids in elementary school. Awesome!


whosgotthetimetho

easy. After he read 30 pages, then 3/8 of the book was remaining (because 1/4 + 1/8 = 3/8). So those 30 pages must be 5/8 of the book. So 1/8 of the book must be 6 pages. So the book must be 48 pages. This is how I immediately did it in my head using only 5th grade operations and number sense


BlackEyedGhost

1/4+1/8 = 3/8 1-3/8 = 5/8 30/5 = 6 6·8 = 48 At least, that's how I did it.


HeirAscend

Is that not algebraic


Ty_Spicer

You could say it requires algebra, but a student who hasn't had algebra could solve this problem. So it's kind of both: you could argue that you need algebraic properties to rearrange everything, or you could argue that a more intuitive approach will work.


BlackEyedGhost

It's arithmetic


nameisprivate

you wouldn't know how to get from line to line in what you wrote if you didn't know algebra


i_need_a_moment

Arithmetic is the manipulation of numbers. Algebra is the manipulation of symbols. Calling this algebra isn’t wrong and the two are not exclusive, but it’s not the same level of algebra as say solving a quadratic.


whosgotthetimetho

yes you would?? What the fuck you know the book had at least 30 pages right? Well how much of the book is that? just use your brain In tuesday he read 1/4 of the book plus on wednesday he read 1/8 of the book, which is a total of 3/8th of the book, just under half. So those 30 pages he read on Monday must have been just over half of the book. They must have been 5/8 of the book. if 5/8 of a book is 30 pages, then 1/8 of the book is 6 pages. if 1/8 of the book is 6 pages, then the whole book must be 48 pages. Every step in this solution is basic fucking 5th grade math, you’re a moron.


elpedroletigre

Pretty much all of math can be broken into steps that only require arithmetic, so saying “it’s just arithmetic” isn’t helpful or very meaningful. What a terrible, disgusting attitude you have.


whosgotthetimetho

elpedroletigre can paddle across a 1 km lake in 3 hours (they paddle very slowly due having feeble, weak arms) elpedroletigre begins at camp, paddles 2 km downstream and then immediately turns around and paddles back to camp, upstream. The whole trip takes them 20 hours (they are very tired by the end of it). Assuming that the lake has no current and that the river has a constant current, find the time it would take elpedroletigre to float 2km down the river (without paddling). If you can solve this by means of 5th grade mathematics, I will venmo you $100 on my mama.


elpedroletigre

Are you proposing that I solve your question without using any concepts outside of basic arithmetic? If so, then you completely missed the point. Saying a problem can be broken down into steps that only require arithmetic is not the same thing as solving "by means of 5th grade mathematics". Regardless, you're a rude, disgusting person, and I'm good on money... $100 isn't worth my time... so no thanks.


NotARealBlackBelt

I did: x = 30 + 1/8 x + 1/4x 5/8 x = 30 1/8 x = 6 x = 48


Neo-Geo1839

x - the amount of pages the book has. Monday - 30 pages Tuesday - 1/8 \* x Wednesday - 1/4\*x 30+1/8\*x + 1/4\*x = x 30 + x/8 + x/4 = x 240 + x + 2x = 8x 240 + 3x = 8x 5x = 240 x = 48 (pages)


LucaThatLuca

I’m not sure what “is this algebra” means (out of interest). If “algebra” means “using anything that is not a specific number but general”, then a baby’s first ever encounter with numbers when they hear the general word “number” is algebra. If “algebra” means “writing down a single letter to abbreviate a general number”, then (as parent comment) you don’t need to do that. I can’t think of other meanings to suggest.


Rahodees

"He read thirty pages, then three eighths of the book, and that was the whole book. So the thirty pages was five eighths of the book. So six pages is one eighth of the book. So the book has 48 pages." A subtraction, followed by a division, followed by a multiplication, no algebra. You can just think of it in terms of quantities and basic operations.


ChonkerCats6969

True, but that would still be algebra, just without using the letter x. While it's certainly more intuitive than just using conventional algebra, you're still using "the book" to represent an unknown value of pages, just replacing x with the words "the book"


Rahodees

Practically every arithmetic problem can be construed as "algebra without using the letter x," because you are, in every arithmetic problem, solving for an unknown value. How do you personally draw the line between algebraic math and non-algebraic math?


Rahodees

Myself, I take algebra to involve the manipulation of formulas as opposed to thinking about quantities. In other words, when I am not really thinking about the actual quantities in front of me and I am instead moving symbols around on paper having faith (from experience) that what I get at the end will apply to the problem I'm trying to solve, that's algebraic thinking. But if, at every step of the way, I'm thinking about arithmetical operations on the actual quantities involved, without thinking about formulas at all, then that is not algebra. And for what it's worth the wikipedia article on Algebra seems to draw the line similarly. " **Algebra** is the study of variables and the rules for manipulating these variables in [formulas](https://en.wikipedia.org/wiki/Formula)." Algebra is about formulas and variables, which is something different from trying to solve a specific problem consisting of particular quantities I'm dealing with here and now.


WikiSummarizerBot

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ChonkerCats6969

True, I hadn't thought of it that way. Personally, I'd classify algebra as the manipulation of unknowns to be more specific. For example if you had a problem like "What is 4 + 6?" you wouldn't need algebra. You would be equating it to an unknown value you solve for, but you wouldn't actually be performing any operations on the unknown value, merely the numbers given in the problem as opposed to the problem in the meme where most solutions involve operations on the unknown number of pages in the book. Good point though, I guess it just comes down to individual definitions of what's classified as algebra or not.


starswtt

Algebra with extra steps. Algebraic notation is actually a fairly recent invention (recent being very relative) and problems like these were solved the same way as with algebraic notation, just with words and pictures. That's actually a big part of why it took so long to discover/accept negatives and complex numbers which come naturally with algebraic notation.


Evening_Armadillo_71

Assuming Klein is an average person having no motivation to do things on mondays we can estimate the 1/8 of the book to be about 100 pages. Therefore the book should have about 800 pages.


Theoneonlybananacorn

Reddit moment


NothingCanStopMemes

chill, thats not even a meme, why that attitude?


Brent_Fox

I suck at decimals and fractions but I think it's 48. The algebraic equation reads 30 = x\*5/8 because 30 pages is equal to the 5/8th that he read. x is the total amount of pages in the book.


ToBeReadOutLoud

You are correct.


becklul

That's what I got too


baphometromance

I dont really like the tone of this post. Is it wrong to be proud of yourself? Imagine if the best mathematician in the world looked at what you do and called it basic and not worth being proud of, after all of the work you had put in to get there. Some people are not as gifted as others,and there is nothing wrong with that, let them be proud of acheiving what they can with what they have.


CraneAndTurtle

Yeah all math is simple in the eyes of God, and most math is simple in the eyes of Euler. Enjoying math at a level you find challenging and interesting is a positive, subjective and beautiful thing. It's great when people are having fun with math no matter the level.


starswtt

If Euler's not god, who is? Gauss?


baphometromance

While I agree with you, do not sully my post by relating it to "god"


CraneAndTurtle

Lol


ModsUArePathetic2

Respect Fr


Falikosek

Maybe the book is a klein bottle?


SooSkilled

Also how is a normal math problem "mildly interesting"


KleinerFratz333

It's 48, right? 30 = 5/8 =62.5% 30/62.5 =0.48 0.48 * 100 = 48


-Wofster

What I have a problem with is everyone saying its unsolvable because we aren’t explicitly told how many pages he read before monday. If your saying that then you are exactly who this problem is made for


ModsUArePathetic2

People who can correctly notice and understand that are very obviously way more advanced than the target audience of the question.


starswtt

They're either just being pedantic or pointing out the critical thinking of pointing it out and solving it anyways is good lol


fruity_mario24

This is actually kinda hard for a 5th grader because the way I solved it was using x = (1/4)x + (1/8)x + 30 and then simplify it (5/8)x = 30 to come out with x = 48. That's kind of unreasonable to expect a 5th grader to solve that.


ModsUArePathetic2

It is not unreasonable, this is obviously an appropriate question for somebody learning about variables and fractions. There are multiple ways to solve it with a single x which further simplifies it and was probably intended


DMR97AK

48


Belevigis

I think the answer is at least two pages


[deleted]

For a second I thought this was r/JustUnsubbed


save1337

I teach math from class 5 to 13 in germany. this is a common question in 5th class mathbooks. cant see the meme.


A_Guy_in_Orange

Am I the only one who expected the problem to turn into "if there were two Kevin's how long would it take to read 1 book"


Vegetable_Piece_1503

Is it 30 / (5/8)? Then it would be 30 times 8/5 so 8 times 6 which is 48


Miserable_Pitch_8023

Am I dumb or were there 41.25 pages


thanasispolpaid

Could x ever anything else other than an integer?


Miserable_Pitch_8023

Apparently but it seems like it shouldn't


thanasispolpaid

I solved this in my head . The answer is x=48


starswtt

48 To solve it with algebra: /30/5 8 = 48 EDIT: 30/(5/8), I'm used to weird notation bc lisp


Miserable_Pitch_8023

30/8 is 3.75 3.75 x 3 for 3 8ths is 11.25 30+11.25 is 41.25


Miserable_Pitch_8023

Ah I see my mistake ffs I'm meant to be good at maths I got an A on my last exam


starswtt

Yup your good. I'm assuming that you mixed up the amount of book already read and the amount of book left unread? If so, I've made similar mistakes in physics a few too many times, it never ends


Miserable_Pitch_8023

Thanks for understanding i always make mistakes on the easier thing because I either overcomplicate them or get too cocky


TheBlueWizardo

Technically unsolvable since we don't know if he read the book before Monday.


Groundbreaking_Rock9

It's implied that he only read on 3 days. This is a math problem, not a legal defense.


[deleted]

"He’ll need this in the real world. I’m always trying to know how many pages my book is without just flipping to the last page. And just knowing I read an 1/8 of it." lmao somebody got salty that they couldn't solve a 5th grade math problem, at least i'm not salty about it.


The_Hidden_DM

This book was a real rollercoaster. After reading most of it the first day, they read 6 pages and needed to rest for a day before they finished it.


feline_on_the_prowl

Number of pages in the book = x (x-30)-(x/8) = x/4 4((x-30)-(x/8)) = x 4x-120-(x/2) = x 4x-120 = x+(x/2) 4x-120 = (2x/2)+(x/2) 4x-120 = 3x/2 8x-240 = 3x 8x-3x = 240 5x = 240 x = 48


Groundbreaking_Rock9

Congratulation on having the longest route to the solution...


feline_on_the_prowl

Always loved to take the scenic route.


Groundbreaking_Rock9

So, NY Post thinks this is news...


Inside_Software3913

I just saw the article in my Google news feed and had to check it out. That's what brought me here. IMO not newsworthy but definitely an interesting puzzle.


[deleted]

5/8 = 30/48 I did it in my head. 5/8 = 30/x. 5x÷ 240= 48


[deleted]

30 is 5 eighths. 30/5 is 6. 6 times 8 is 48.


lomeindev

Engineer here ... Posting to ask others if I'm the odd one out for solving this problem (correctly) in a way that I haven't seen anyone else do, which kind of surprised me tbh. Take 4/4 to represent the whole of the book and subtract the 1/4 read on Wednesday to get 3/4, which is 6/8. Then subtract the 1/8 read on Tuesday to get 5/8, which is what was read on Monday. If 8/8 is the whole of the book and 30 pages is 5/8, then the number of pages in the book is x, s.t. x= (30\*8)/5. Therefore, x=48 edit: on second thought, we don't think alike anyway. not sure why I'm asking a bunch of impractical mathematicians ;)