The Wrong Way To Reduce Fractions. But It Works Sometimes

This is a joke video about mathematical coincidences. I solved a bunch of fractions problems but my teacher didn't like my answers even though the results were 100% correct.
It's called anomalous cancellation.
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[@dragan176]

I LOVE that you said "my teacher clearly hates me" because this perfectly describes these sorts of mentalities!

[@nathanbeer3338]

The dark secret that teachers don't want us to know.

[@TheDiamondGames]

Watch this video before it gets banned.

[@takwan2884]

lol

[@glitch4010]

this and the triangle rule... xDD

[@baronhelmut2701]

No it actually only works on prepared examples. Not on every single example.

[@sirbillius]

Ya know like how graphing calculators works.

[@RSPikachuAlpha]

0:55 “For the fifth problem,” *moment of silence* “I looked at...”

[@GameFlameonYoutube]

19/95 also works

[@crazyworld4161]

😂😂

[@aashsyed1277]

No

[@not_pockchan3418]

@@aashsyed1277 yes it works, 19 * 5 = 95

[@sripavanch4085]

19/59 =

[@dannyluo2077]

@@sripavanch408519/59 is in simplest form (in fact, 19 & 59 are both prime numbers). Btw, here’s another example of this wrong method producing the right answer: 127/762=1/6

[@lostlong62]

Lesson learned: People take things way too seriously... It's so obvious that he made this video so we could get a laugh, considering that the other content he posts are very serious and further into math than this simple video of "reducing fractions".

[@Manta2006]

Still alive?

[@peterg.mainetti9871]

It's hilarious how some people think that this video was being serious and are all triggered in the comments. READ THE TITLE AND DESCRIPTION, PEOPLE!

[@Niko_demus]

The only interesting question is "why does it work?" and it's not even asked.

[@CaptainMonkeyFez]

It doesn't.

[@philipmalan4967]

21/12 is not 0/0 XD

[@Poirot633]

+Alexander N. Benner (Nikodemus) As usual on this channel, the most interesting part is left apart.

[@Niko_demus]

BTW.: next to the obvious picks like 2/12 or so, even fractions formed like those in the video don't work: 37/71 for example

[@xxJokinxx]

+Alexander N. Benner (Nikodemus) this is probably just a coincidence, i have tried with other fractions and it doesn't work at all. The fractions have probably been chosen to work.

[@atharvapande1373]

How about 31/13 ????

[@tranhai_Huytracomeco]

3/3 or 1/1

[@unbutteredtoast6412]

Read the comments section above, someone explained the "why this works" aspect.

[@_1strike1_86]

U can't make that smaller in any other way😕😑

[@Reality_recheck973]

Only proper fractions works

[@maqshood]

Atharva Pande i think the probability of his trick working is when the numerator is smaller than the denominator

[@TimJSwan]

Your teacher should have given you extra credit for finding out that his set of example problems were perfectly broken.

[@bgpcusercheater5174]

bruh no noob

[@alpistein]

Guys lets just put it this way: There's a reason why he chose these specific fractions. For all of you saying this is misleading, look at the goddamn title. "The wrong way to reduce fractions." That's a statement, he's telling you it is wrong. "But it works?" That's a question, he's asking if it works or not. It is meant to arouse your curiosity, he's not trying to mislead you. Chill out.

[@KingDuckSauce]

Shut up lil bro 🥱🥱

[@akbaer60]

This is really hilarious At the first glance, i thought this was a serious video. Then I realized this was all just a joke and a coincidence.

[@amichaelthomas83]

The more interesting question is what percentage of fractions within a certain range (of denominator and numerator) satisfy these conditions.

[@Vazhaspa]

Yes that is exactly correct!! We know that Max Planck was once working on a "fraction" over a function of r [namely f(r)], so he canceled out "f &r" from numerator and denominator and arrived at the quantum of "action"!

[@youarebeautiful9050]

aaah this comment is so underrated 😂

[@sniperfuazo6495]

lol it work but your teacher just hate you for being way too smart

[@Thesamurai1999]

It doesn't work with all numbers, that's why it's a horrible method as it's not guaranteed to work. A genius can make something that'll awlays work.

[@sniperfuazo6495]

Link i know but this video just make me laugh

[@sniperfuazo6495]

Link sorry for the spelling tho i not a american

[@Gamer-uf1kl]

@@sniperfuazo6495 english is not american, english comes from england. ENGland ENGlish.

[@SirBartolomew]

Congrats, you've managed to make the video with the most disgusting and ignorant comment section I've ever seen. Great video, though. Keep it up!

[@jeaniebird999]

You must be new to KZbin. This comment section is quite low on the Disgusting and Ignorant scale, compared to what's out there. If that's what you're looking for, you can go just about anywhere else.

[@gulgaffel]

+Guilherme Exel Go to any video discussing religion and i tell you it is much more disgusting.

[@culwin]

+Jeanie H. A. (jeaniebird) Your avatar is kinda lame

[@jeaniebird999]

HOW DARE YOU! Come over here so I can kick your ass! Hey,... you look like me... Are you my long-lost twin? I've missed you so.

[@ralphinoful]

This happened while I was tutoring a kid. We were trying to find the area of a regular pentagon. And the answer was like... 5.23...something, but rounded to 5.2. He got an answer of 5.18...something, randomly, by doing something incredibly stupid. I then told him he was wrong, even though he had the right answer. He got really heated, and kept telling me, "BUT I HAVE THE RIGHT ANSWER, HOW THE HELL AM I WRONG???"

[@Kebabrulle4869]

+Ralph Strocchia The struggle of being better at maths than someone else.

[@livedandletdie]

+Truls Henriksson The problem is people dislike people that cut corners. I never got that good math grades in school, but I solved the problems 5 times as fast as the other students, but got Fs because my documentation of how I solved the problems were non existent. That's what one gets when your brain subconsciously calculates everything it sees.

[@someone6949]

+The Major sounds to me you were doing something wildly different than what Ralph was talking about and what was in the video. To me, it sounds like you were doing everything a correct way without showing work. The student Ralph mentioned was said to be doing it obviously wrong and by pure mistake got the correct answer.

[@ralphinoful]

The Major Doing the correct thing, but not documenting it is a lot different than the scenario i explained. The problem went something like this. A regular pentagon's area has a 5.21 (Random numbers) ratio compared to the length of a corner to the center of the pentagon. And you were given one side length. So you had to use The Pythagorean Theorem to find the length of the line connecting the corner to the center, and then multiply the value of that line by 5.21. But in his case, he just took the given side length, and multiplied it by 5 because "There's 5 sides on a pentagon." And that answer happened to round down to the correct answer by coincidence.

[@westwolf48]

+Ralph Strocchia Sounds like an unfortunate case. The right thing to do in that situation would probably be to generate a problem for which their solution doesn't work, and reason through the solution together. If you can't get a few minutes to come up with a counterexample (they're really frustrated), get them to help you generate the counterexample "Can you think of a situation where this wouldn't work?"

[@brucewaters1617]

ITS A JOKE EVERYONE CHILL YOURE ALL HATERS OF COURSE IT DOESNT WORK

[@captasticts8419]

@Zero Flower what

[@malte291]

You don't knoow why? But he talked to you after class.

[@nixdorfbrazil]

Ok... So it "works"... but I don't understand why it "worked". I read the Wolfram link, and still doesn't make any sense. Is this just a mathematical coincidence? Or there's some logic behind it?

[@MindYourDecisions]

Yes, it is a coincidence. There is a mathematical way to derive such coincidences as well, which is how some of these are known.

[@supermushroomDX]

+MindYourDecisions It's called an anomalous cancellation.

[@TheF41thfull]

+MindYourDecisions It made me laugh. It would be great to explain that when you can prove it for a set of instances and formulate the rules, you create a calculus. And then we can let the symbols do the work :)

[@Unstopapple]

+Nix Dorf it works, but not for all problems. This is a very limited set of rational numbers that can have this done to them.

[@heyitsalex99]

+MindYourDecisions what is the mathematical way to derive them?

[@jojogape]

Even though this is obvious to a lot of people... mayyyyyybe you should have explained that these are just coincidences, and the rule very rarely works. We're used to finding "Videos With Revolutionary Methods To Solve Math Problems" so a lot of people might end up believing this video no matter how incredible it is. I mean, the moment they told me the sum of every positive number was -1/12 I just gave up. Edit: I see the title now. I don't know if you recently changed it though. Anyway, good thing somewhere you can see that this method is wrong.

[@djthebeastmusic6603]

+jojogape this is the case because of the riemann rearrangement theorem which states when you rearrange a series it converges against some number. Some physists did a wrong rearrangement, this is how this statement was created

[@MarcusAndersonsBlog]

+jojogape There is a conjecture in string theory that attempts to perform algebra on infinite series that arrives at this result (-1/12), a very convenient result that allows them to make other fantastic claims. Confirmation bias and a desire to understand quantum mechanics has a lot of mathematicians overlooking the fact that you cannot take the difference between two non converging infinite series because the result of both is undefined. its like saying infinity minus infinity is -1/12. Like this video, its a coincidence. There's lots of coincidences in numerology. Party trick material only.

[@jojogape]

Exactly. It's like some sort of "Mind-Blown Effect", when most people watch this video they're like "WOW!! THIS IS SO IMPRESSIVE!! Must share with everybody so that they know as well... and BAM. Instant views." In other words, this video is pure clickbait. And it's frustrating because I used to respect this channel a lot.

[@ignantxxxninja]

+jojogape this should be top comment

[@MarcusAndersonsBlog]

+SpaghettiToaster I don't actually think I asserted "working mathematicians are morons", however I'm inclined to make an exception so far as String Theory is concerned. ;-)

[@MTW144]

He: reducing fractions and end video Me: Closes KZbin and opens Photomath to check.

[@alexzuma2024.]

teachers be like: your answer IS correct, but, you simplified those numbers the wrong way!

[@Jolly789]

Math is Magic.. it's amazing and so exciting.. I love maths..

[@w1swh1]

Magic it certainly is! It really is the only 'Universal' language.

[@jastid5294]

"works sometimes" this is literally me

[@ArnabAnimeshDas]

Actually, you might call them co incidences, but I call them the beauty of decimal system. That's why I like numbers. It's like the universe. The more you intend to understand it the more you come to know of the surprises it has in store for you just waiting to be solved.

[@ArnabAnimeshDas]

+Nui Sance It's obvious because all those numbers will be evidently divisible by 3, because you are taking 6 as the base. -_-

[@Unstopapple]

+Arnab Animesh Das So 5 is divisible by 3

[@ArnabAnimeshDas]

+GenOmega2 Please explain your logic behind that conclusion of yours

[@mzg147]

+Arnab Animesh Das Sorry, but you are soo wrong in my opinion. There are just coincidences, no beautiful at all. There are many incredible connections, theorems and fantastic thoughts in mathematics, but you choose to adore some rubbish facts. It's a disgrace.

[@ArnabAnimeshDas]

+mzg147 Well, it's a matter of perspective. I find that determining coincidences anywhere is interesting. Some coincidences require little knowledge to see, some require a good amount of knowledge to see. Like here in this video, it's not easy to come up with large fractions which can be reduced to its simpler form by simply scratching out common digits, whereas someone may accidentally come up with small fractions. It's similar to why we like the date 12/12/12. Finding out and/or proving a generalized statement regarding coincidences is also praiseworthy.

[@-fewkey-2362]

That's how my math teacher also taught us. She calls it the shorter way. But we did it with adding, subtracting, Multiple, and division with it.

[@guilhermeteofilocachich4892]

Nice video! But always remember that if it only works sometimes, it's not math. It's luck.

[@merveilmeok2416]

I laughed so hard when I saw this video and I am still laughing 😂 😂❤️

[@warpromo6636]

I use that method sometimes when you are able to, this kid used it in front of the teacher, and the teacher told the kid "Where the hell did you get this from?"

[@warpromo6636]

I also used this method on a test where you needed to "show your work" on basic fraction problems, she marked the questions wrong that I used the method for.

[@beepbeeplettuce2779]

I hope you're kidding.

[@tychophotiou6962]

To find these examples must be so hard. You have to be a brilliant mathematician to find examples that do this!!!

[@oki5297]

bro hasnt heard of code

[@taoxkai]

What did the teacher say?

[@XloreX50]

It's just a story he made up

[@deadpaul6587]

Kai Urwin succ

[@ArattaTube]

Teacher said: Please teach me the tricks !

[@captasticts8419]

@@SorakaOTP462 chill

[@johnallen1901]

OK, for all rational numbers a/b where 1 < a < b < n, what is the percentage of numbers for which this trick works when n = 100? When n = 1000? Bonus: Does this percentage have a limit as n approaches infinity?

[@gtorp9397]

why are people taking this so seriously

[@arda9437]

It's common core, even though the answer is right, but how you do it is wrong, it's wrong. For example: 5 x 3 in common core is 5 pieces of 3s, so 3 + 3 + 3 + 3 + 3 = 15 Some kids answered 5 + 5 + 5 = 15, teachers says wrong. Parents are upset after this.

[@1997CWR]

Since 36/65 != 3/5, you way of "solving" equations only works in some special cases and is therefore useless

[@damienw4958]

Just a heads up, don't put !'s in your maths work, as it means factorial (which, for anyone that doesn't know, is denoted as n! = (n)(n-1)(n-2)...(3)(2)(1) ) therefore it can be misleading in cases where factorials are appropriate. Luckily for you, it was obvious you didn't mean that so this is just a friendly note for you for the future (don't want to make this mistake in an exam or something! :P)

[@damienw4958]

Just a heads up, don't put !'s in your maths work, as it means factorial (which, for anyone that doesn't know, is denoted as n! = (n)(n-1)(n-2)...(3)(2)(1) ) therefore it can be misleading in cases where factorials are appropriate. Luckily for you, it was obvious you didn't mean that so this is just a friendly note for you for the future (don't want to make this mistake in an exam or something! :P)

[@F2L4Life]

+Damien W "!=" is also programming lingo for "Does not Equal". He used it correctly for the purpose he intended.

[@magicgamegx]

+F2L4Life Isn't "" the more widely accepted term for does not equal? I know it's different languages but just curious.

[@1997CWR]

Yeah, it depends on your programming language. Java uses !=, but Python for example uses both.

[@santinodemaria2818]

This is the very first video that i watch him just showing us a fun "math" game

[@ashaydwivedi420]

OK, so it's a December's Fools now

[@manojRao7]

this channel should have a million subscribers

[@gokublack.7417]

Thank god my maths teacher was my friends neighbour so he knows me well so he likes me and cares me

[@Fitnessdickinmymouth]

Me: Gets a calculation right but I don't do It her way teacher: gives me an F me: Math is Math

[@jasondeng7677]

i'm waiting for someone to be WOOOOSHED

[@myrus5722]

Random Chicken Look at literally any comment on this video

[@jasondeng7677]

@@myrus5722 Yep. Now i'm using copy and paste, it's so bad

[@multitalentedsf4350]

Thank u so much i searched this for 1 hour and finally its only with you

[@DarthAlphaTheGreat]

This is where the NSA come in. No, not the National Security Bureau, the NEVER, SOMETIMES, ALWAYS examples. Does this work always? If yes, then it's fine. If never, relearn everything. Sometimes? Let's find out when it fails, and WHY it works here but not elsewhere :)

[@gtorp9397]

and this is where the description comes in

[@DarthAlphaTheGreat]

I know. Hence my comment what should a teacher do if the kids want to troll you.

[@ritastanaitiene3479]

It works ALWAYS

[@JayLKing]

what if you get something that's like: 156 divided by 872? There are no common numbers, so that would not work, right?

[@TomMaynard--TCM--]

@Sid Hollander That seems a bit harsh. You can't expect terrific bids that satisfy each and every time. Hollywood would be doing a whole lot better if that were the case. I kinda liked this one myself ... Presh always gives one solution, and leaves you with a puzzle/problem to solve on your own (Why does his teacher hate him? For not showing his "work" -- aka "derivation of the answer"). You're free to subscribe (or not) as you choose, but unsubscribing means you'll miss any future gems/goodies he might produce.

[@MindYourDecisions]

Thanks, I was thinking of writing a comment along these lines. After all, the name of this channel is "mind your decisions."

[@simonshugar1651]

obviously not the best at spelling

[@JoelReid]

I once solved a very complex problem that had logs all the way through just by removing all the "log" and leaving the numbers and letters. My teacher was not impressed... but the answer was right. These coincidences happen all the time.

[@shykiu5366]

well.. thats how you do it with logs...

[@ophello]

Thanks for explaining absolutely nothing.

[@deathwing9664]

Thanks for not reading the description or the title....

[@aktan4ik]

Thanks for the meal I'm fortunate to eat without fearing that it might be my last one.

[@apatriot6421]

R/wooosh

[@benjaminbrady7801]

This new trick is leaving [insert location here] mathematicians stunned.

[@jabbablade1884]

Maybe teacher hates you because you aren't solving homework on his way :)

[@vousvxyez]

My man out here *_finessing_* math teachers

[@nickjs5773]

Your teacher didn't hate you, quite the opposite. The "F" wasn't for fail ;) "SEE ME AFTER CLASS" should have emphasized that point.

[@morning5tarr]

Creepy

[@apatriot6421]

People like you want to see the world burn

[@commentatron]

Your teacher is in good company.

[@tintinfan007]

this is just a mathematical coincidence. there are lot of other examples too : for example, the square of 12 is 144. at the same time square of 21 is 441. do u see anything remarkable ? 12 and 21 are palindromes and so are their squares. the same thing goes even for 13 and 31. but then it does not hold good for 14 onwards

[@skylarkenneth3784]

The pattern I'm picking up on is depending on whether the first number of the denominator is ticked off. If it is, then moving an left to right, you mark off the corresponding number from a right to left fashion on the numerator. If it isn't ticked off, then you move in left to right fashion on the numeration and do the same thing.

[@skylarkenneth3784]

If you happen to mark off every one of them, then it's either a single digit or prime... maybe the number of digits affect it as well? I'll try more, this is very interesting :)

[@sibashankarsahu2055]

123456789/987654321 what will be its answer.

[@Kayroten]

ihihii

[@TheHeroOfMC]

"1" is the answer. A Whole number not a fraction

[@axelhowardcalonge6361]

TheHeroOfMC I suppose you're joking, right?

[@TheHeroOfMC]

I was being sarcastic lmao +Axel Howard Calonge

[@soupdetomat2146]

bloggingidea hub Obviously 1/1

[@xaytana]

I noticed a pattern; the denominator moves one digit from the numerator, either left or right, or moves right and the number is treated as a circle: far right moving right becomes far left. But also notice that the ending fraction has the numerator and denominator one digit apart. But this only works if it's a multiple of a simple fraction. I think what we have here is just a coincidence. I don't think there's any formula to show how this works, and don't think there ever will be. Edit: it's all a coincidence with very specific numbers.

[@sidhollander949]

Your teacher is not alone. Some of your videos are so good. And then others are, like this one, in absence of quality appear to be put out by you only build and bilk subscriber views and I guess to build either your $$$ for views ot your ego. I will no longer subscribe because of this..

[@fernandopizarrovillagarcia6992]

As a curious fact, the numbers eliminated in the examples are all multiples of 6. Is it also a coincidence?

[@MrGerrymagic]

18/89 does not equal 1/9

[@CH3LS3A]

Q.E.D.

[@julianbueno6316]

MrGerrymagic you use this in a test right?

[@want-diversecontent3887]

MrGerrymagic 8 is not divisible by 9

[@want-diversecontent3887]

ChunArt Chun Sorry I mean divisible by 3

[@jasondeng7677]

it's a joke

[@sergio73master1]

It's kind of the same of saying: "2+2=2*2 So multiplication and addition are the " It's just a coincidence. It defenitely a coincidence...

[@Shadi677]

42/44 following your rule will equal 2/4 which equals 1/2 which is obviously wrong it should be in the simplest form as 21/22. i think this method is a special case for special fractions like in your examples. we cannot generalize it as a rule for every fraction.

[@bengtbengt3850]

Thanks captain obvious

[@fatman3762]

Did you even read the title of the video?

[@fatman3762]

Warren Dominic Beltran No it just only works in special cases that MindYourDecisions made for joking clickbait (There is no pattern or reasoning for this because it's made up entirely)

[@want-diversecontent3887]

Shadi Rizeq But 4 is not divisible by 3.

[@want-diversecontent3887]

ChunArt Chun Because in the denominator, there is no 42, only two 4's. So you can only use 4. 4 is not divisible by 3.

[@izzabelladogalini]

I've seen people use specific instances to try and demonstrate a "rule" or even a "proof" and are seriously trying to convince the viewer.... fortunately I've seen a fair bit of other content from Presh so I know in this video his tongue is firmly in his cheek.

[@brianyun249]

Yeah, and of course 123456789 divided by 987654321 would give you 1 then, huh.

[@The-1-Ring]

it was 12345679 / 98765432. So it makes sense that it = 1/8 and your comment is BS

[@Macmo0699]

+Corneliu Bondarenco Brian is saying that IF the question was 123456789/987654321 and you used the method used in the video, the answer would be 1. Which is obviously incorrect, your comment is BS

[@yokowasis]

Because the most important thing is not the result, but the process.

[@pavlossakoglou4435]

The smart and correct way to reduce fractions is to express numerator and denominator to their prime number components (by the fundamental theorem of arithmetic), and then cancel out the same prime numbers that appear in numerator and denominator. Example: 330 / 2310 = (2*3*5*11) / (2*3*5*7*11) = 1/7 But canceling the same numbers in numerator and denominator doesn't work for composite numbers -- it's luck that it worked with these numbers in your video, hence you deserved an F. It's like randomly answering a hard question that you have no idea about, and get it correct nevertheless. That moment's luck shouldn't qualify you to pass the test.

[@beepbeeplettuce2779]

boi read the goshdarn title and desc. Seriously though, it should be rather obvious that this is a joke video. The fractions were specifically chosen to work.

[@i_am_anxious0247]

Pavlos Sakoglou *I T S A F U C K I N G J O K E*

[@jasondeng7677]

woooosh

[@geetaagarwal4622]

19/95 9 cuts 1/5!!

[@Goabnb94]

Your teacher failed you, because as somebody who marked exams at university, we don't give a shit about what answer you come to. We only care about how you get there. And if its logically sound (generally the way we taught you, but other logic works too), you get more marks than writing down the right answer. Because teachers are there to teach to methods, not right answers. You got to the right answers in this case by luck. There is no logical step by step process for doing this, nor have you explained why it works. It just somehow worked, which is contrary to what the teacher is trying to teach you.

[@franzluggin398]

+Goabnb94 He did get an F in the end, which is the worst possible mark, he just _expected_ to get an A.

[@MsHojat]

I generally disagree with this. If a person is getting answers right, if they aren't cheating the method they arrived at the answer doesn't matter. Showing work should be for people who want partial credit of they get a wrong answer. If someone is using a wrong method, the answer will almost never be correct, so it shouldn't matter to see what the method was used. If wrong methods would work in life, then there would be no need to learn the proper method in the first place.

[@Goabnb94]

Mshojat But if they are just getting the answer by luck, using a method that doesn't work most of the time, they get the answer by luck, not because they know what they are doing. School doesn't care about the right answer, they care about knowing how to find the right answer. Its especially relevant for more complicated math.

[@MsHojat]

Goabnb94 Note the part where I said "if someone is using a wrong method the answer will almost never be correct". If they get an answer right by luck it doesn't mean anything, because they got the other 99 wrong, and the got a failing grade. It's not like it's easy to accidentally get a right answer with a wrong method. For most problems it's extremely difficult and extremely rare. Do you understand what I mean? I fully understand that it's important students learn the right way to do something, but that is 100% directly correlated with learning how to get the right answer. It's simply impossible to consistently get the right answer with a wrong method. When a teacher is initially teaching a new concept, he would want to make sure the students understand the process, but when it's time to test them, it's all about testing. Testing is seeing if the right outcome can be obtained. Aside from cheating, a right answer IS a right method, 99% of the time, and the 1% or 0.01% of the time that it isn't, it does not matter whatsoever.

[@franzluggin398]

Mshojat This works for real-life example data, which is probably sufficiently random, but many tests have a special set of solutions like 1, 1/2, ..., everything rational and only some very few solutions that are irrational, e.g. solving x^2+4x+2=0. That is supposed to give the students a feeling for whether they are right or wrong and make them less likely to fail due to some miscalculation that has little to do with the topic of the exam. And yes we understand you. But I at least cannot agree with you, because giving people points for the right answer but NOT giving them 0 points for the wrong answer is just being inconsequential. Either the solution is important to you and the wrong answer gives 0 points or learning the concept is the important part and not having applied any logical concept (not necessarily the one you taught, but a logical one) is worth 0 points. As far as math goes, I would say the solution is unimportant because math is not about the knowledge of the solutions (unlike other lessons that teach you a list of things to know and there is no logical way to derive one bit of it from the previous) but about the knowledge of how to apply methods to get to said solution.

[@robertej09]

I think it's hilarious how so many people took this video seriously. The title literally mentions that it's the wrong way to reduce fractions, and that it "works" sometimes.

[@bananaforscale1283]

12345/67890 good luck

[@lilygierula5885]

Bananaforscale 823/4526

[@Nerketur]

Is there an algorithm to create these problems? Or even a subset of these problems?

[@medexamtoolscom]

Well if you could just do that, then 163/326 would be the same as 136/326 or 631/326, and in fact all integers that are just permutations of each other would equal each other, since the denominator is the same each time and you're just changing the numerator by making them permutations of each other.

[@spencerhiginbotham7538]

You'd have to be pretty lucky to get six questions right if you do it this way. If my student did that, I would probably think they cheated.

[@farpointgamingdirect]

Whenever I had a different way of doing something and my teacher gave me crap about it, I would tell her to stick it in her ear and tell her to complain to my parents if she didnt like it; my dad would invariably tell her to stuff it and ask her why she cared as long as I had the right answers and could show my work. (Because, guess what? This us the method they teach you in algebra!)

[@chapmanchapman3994]

Why most of comment do not find "how to make this method workable". I just find relationship for 2 digit. ab/cd work only if b/a+9 = 10c/d. I think it is not difficult to find the relationship on more digits.

[@powerhouseofthecell9758]

Turns out it wasn't Math at all, but a psychology intro you forgot your class was doing.

[@sup3rk3wlp3rson]

I think you could of got more views with a title like "Kid Figures Out One Simple Trick To Division - Math Teachers HATE HIM >>> GONE SEXUAL SOCIAL EXPERIMENT

[@murthybhaskara1117]

This method applicable in Very limited way where the digits of numbers cancelled are different in numarator and denominator. It doesn't work mostly like 24/42, 36/63, 124/248 ...a few

[@buildersmark3231]

and how about 743216789/6789564321? but the answer is not 7/56(1/8),can you tell me why?

[@buildersmark3231]

question, how about 63874219/96387421? if use your way to solve it, the answer is 1. but if use the calculator to solve it directly ,the answer is 0.662682104... why?

[@EarlJohn61]

Because those two numbers are mutually prime... 63874219 can be factored out to 17 x 19 x 197753 which are all prime numbers Similarly 96387421 can be factored to 13 x 7414417 which are also prime numbers And it is obvious these have nothing in common... You can get an extremely rough approximation by ignoring all but the first 3 digits in each number this gives you: 638 / 963 which using Prash's faulty method would give you 8 / 9 which is closer but still wrong... (& that's the point, Prash's method is faulty... NOT because it works SOMETIMES but because it doesn't work MOST TIMES!!!) [Note that the single digit approximation 6/9 is closer than the 3 digit approximation and can give you an indication of the final number BUT IT IS STILL WRONG...] Prash was given an 'F' NOT because of the answers but because of the METHOD used! [I suspect that Prash was bored out of his brain and was trying to wind up the instructor! Successfully it would appear!]

[@hotdogskid]

there was a pattern with all of the fractions. the cancelled out digits were always shifted one to the left or one to the right. i dont know if thats why it works or not but thats what i noticed

[@anniepark6694]

But how do you know what values to cancel out?

[@MysticOrangeCaramel]

thank you for teaching me the easiest way! I have a big test tomorrow but thank you!

[@zbodle]

GL on your test. Hope you'll get at least one answer correct this way.

[@Chocolatebutterjelly]

If I were you, I'd look a bit more into this before blindly using a technique that a youtube video taught you. From what I can tell, the equations in the video were specifically picked to work with this method, and probably don't really work in others. Just stick to the normal way, if there were an easier way, I'm sure your teacher would've taught you.

[@BakaBaka8146]

+TheBlueSquid well in description he said it was a joke. i dont think someone will use it for real in test

[@SuperSmashTails]

What do you do if you get 42424/64242 ?

[@TheMemer_]

First time heard Presh' humour 😂😂😂😂

[@iwersonsch5131]

I was somehow exspecting a puzzle on _how often_ this is going to work. It might be too hard for a puzzle.

[@user-iq6fn5cm7q]

HOW TO SIMPLIFY FRACTIONS THE EASIEST WAY: If the difference between the numerator and denominator is 1, the fraction cannot be simplified. A. Ask: does the numerator go into the denominator evenly (i.e. without any remainder)? If yes, proceed to B. If not, proceed to C. B. Great! The simplest fraction is 1 over the number of times the numerator fits in the denominator. (e.g. 20/60, 20 fits evenly 3 times, hence 1/3.) C. Write the remainder, (e.g. 20/46, (20 fits 2 times in 46, with a remainder of) 6.) to the right of the fraction, and ask: does the remainder go evenly into the numerator? If yes, proceed to D. If not, proceed to E. D. Great! The "remainder" is the Greatest Common Factor. Divide both the numerator and denominator by the GCF/remainder to have the simplest fraction. E. Write the "new remainder" (using the last example, 20/46, 6 fits into 20 with a "new remainder" of 2) to the right of the previous "remainder", and ask: does the "new remainder" fit evenly into the previous "remainder" (2 into 6)? If yes, proceed to D. If not, proceed to E. Please, (with your amazing talent,) produce a video demonstrating it. //Euclidean Algorithm.

[@Peter_1986]

You got an F because it's not the answers that matter, it's the procedures used to get to the answers. =P You can get points for a question even if the answer is wrong, as long as your steps to get there are correct most of the time.

[@lelouchvibritannia1410]

The entire problem with the system is that you have to find the solution "systematically". You can't find a loophole. This pisses me off 'cause no matter how you come to the conclusion it's the answer that matters.

[@kingjimmycraftofcalderonia2017]

How often does it works?

[@anonnomus6070]

at least 6 times my friend possibly more

[@tabeenasif3238]

What if you have two left in denominator and three in nominator. How do you arrange them?

[@Maxmilian666]

Where is the conversation with the teacher?

[@AA-100]

This also works with 19/95 = 1/5

[@achluthfi]

how about 24/48??? it must be 2/8 with that method, but it must be 1/2 with calculator.

[@jasondeng7677]

bro, this a joke

[@randomlyavery3210]

What if the pebbles doesn't have the some of the same numbers as the numerator and denominator? Is there a cool trick for that too?

[@conclusionakayogesh9055]

Could it will be possible if their would be addition or subtraction instead of multiplication

[@phildurre9492]

would have liked this video if you gave annexplanation to when it works and when not

[@jasondeng7677]

dude, it's just coincidences!

[@abcrtzyn]

Technically, you are correct because if you put two numbers together like 2 and x, "2x," it means multiply. So writing 32 should be 6.

[@ProfDragonVale]

It case you didn't know, you can multiply the digits of multiple-digit numbers in both halves of the fraction and you will still get an equivalent fraction (unless any of those digits are 0). So, 16/64 can be seen as 1x6/6x4. Based on basic properties of division, that is equal to 1/4 x 6/6. Because any number divided by itself is one (n/n = 1), the 6/6 can just be written as 1, leaving you with 1/4.

[@ProfDragonVale]

Doesn't always work, it just works here

[@ProfDragonVale]

+LordKelvin100 I know, I corrected my mistake, I was just explaining the coincidence he was showing

[@SomnathPattnaik]

Those who have studied Chemistry from Pankaj Sir (Physics Wallah) they know this already 😂🤣😅

[@tangzhang1087]

So, when does it work?