World's Toughest Riddle Explained

Where did the extra money come from? Learn the answer to the problem stumping people around the world!
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[@rsuresh4396]

I have ₹5000 Spent:0 Balance:5000 Spent:0 Balance:5000 Spent:0 Balance:5000 Spent:0 Balance:5000 Now explain me from where I got ₹20,000... this is what happens if you add the balance column...

[@imsbarman]

Good

[@gabriellthegamer7614]

Thats what i thought

[@HimaniSahu.]

@@gabriellthegamer7614 ur bs tag?

[@utalmighty]

This explains me more than video did.

[@HimaniSahu.]

@@gabriellthegamer7614 wanna play wid me?

[@user-be6wh5rz4j]

How About *I Have 50* *1st Spend = 0 | Balance = 50* *2nd Spend = 0 | Balance = 50* *3rd Spend = 0 | Balance = 50* *4th Spend = 0 | Balance = 50* *Spend = 0 | Balance = 200* *Thats How You Got Rich😎*

[@jak7062]

Lmao , man you got me. That was funny

[@balachandiran8126]

Ha ha ha 😆😆😂😂😂

[@zohakhan7402]

😂😂👏👏👏Wow

[@isaacsteffen9050]

I was just gonna say somthing like that

[@deeppatel8276]

🤣🤣🤣🤣, ya good explanation

[@jensraab2902]

The toughest question for me that's arising from this problem is why anybody would even add the balance column, let alone expect it to match the original amount.

[@billyfraiser6298]

And yet you're here. The irony in your comment is astounding...... which I find to be the toughest question of them all.......¯\_(ツ)_/¯

[@jensraab2902]

@@billyfraiser6298 Why should I not "be here"? I didn't know what the video would be about, hadn't seen this problem before. Admittedly, I didn't study the table on the thumbnail, I just saw that it in my feed and because Presh has many interesting videos and I had 4 minutes to spare, I watched. Then, I commented on it. What's so strange about that?

[@Kyle-nm1kh]

It is illogical to add the balance. What if you spent 1 dollar 50 times. 1 + 1 etc = 50. How come 49 + 48 + 47 etc doesn't also = 50? Makes no logical sense

[@jensraab2902]

@@Kyle-nm1khThat's my point. There's no reason to expect that the sum of the various balances add up to the original amount. The example that apparently "stumps people around the world" as Presh put it, is carefully designed to present a problem that isn't one. Where mathematically illiterate people start wondering about where the one extra rupee comes from, those of us who understand math start wondering why on earth you'd want to add up the balances in the first place. 😅

[@jonathanjonathan7386]

@@Kyle-nm1kh indeed, it's just a bit of magician's misdirection , presh got the figures as close as he could to 50 to give the impression that adding up the balance was a valid operation and asked the question were did the extra money come from.

[@o_sch]

Figured it out right away “why are we summing the balance?” And then tried a scenario where you spend 1 every time and realized its pointless because it will be 49+48 on the very first cycle

[@pegasus-gj4te]

fiinally a good explanation, thank you

[@jimmyc2001]

The simple answer: Summing the balance column is just a nonsense.

[@13hasratpreetkaur42]

🤣🤣🤣🤣👍👍

[@lololololol1342]

Exactly. That's kinda the whole point of the problem

[@Osirion16]

Yeah, I thought about the same thing... Not the toughest riddle at all...

[@xandermichels8336]

wish it was, spend one penny be a millionaire

[@falfa3370]

Exactly i made my family believe me using a new form of example smh

[@fabianwascher1384]

You have $50. You spend $50 and the balance is $0. Where did the money go?

[@noverdy]

lmao this somewhat made me laugh

[@potatok123]

Student debt

[@francescocernecca3176]

@@potatok123 lol.

[@Mrwiseguy101690]

Food

[@Sora-pk7wg]

😂😂😂😂

[@SharkyShocker]

My favorite tactic is "Same Problem, Different Numbers" and it works well here. Just change the problem so that each time you're spending 10, and you quickly realize (with a balance add up of 100) that it doesn't have to equal the original balance at all.

[@neetugupta1484]

Others: thinking from where did that 1 ₹ came?? me: feeling proud that he used ₹ for example 🤣

[@vinodkumaragrawal2988]

Yeah

[@vinodkumaragrawal2988]

Indians op

[@sandhuekam14]

Hes a indian lol

[@samarthsaxena2053]

I was just going to write same comment Then watched urs and liked it

[@montayhuber5871]

Fool

[@ArtinTheBeast]

Let's reword the problem and create a similar one: I have $50. I spent $1, now my balance is $49. I spent $2, now my balance is $47. I spent $47, now my balance is $0. Total spent=$50. Total balance=$96. *Where did that extra $46 come from?* Notice how the "spent" category will always add up to $50, but the balance category won't necessarily. That's because adding up the balance is a completely illogical move in order to determine how much money you started with.

[@iblamelance5350]

Artin Why did you add up the 49+47 lmao that makes no sense in your example

[@ArtinTheBeast]

@@iblamelance5350 That's literally the whole point! The point I was trying to make with that example is that it doesn't make sense to add up the amount of money you have left in your "balance" category. It seems you've misinterpreted the purpose of my comment.

[@TuberTugger]

I have $50 I spend $50, now my balance is zero. total spent = $50. Total balance = $0. But I do have 1 hole in my pocket. So there's that.

[@ahgflyguy]

wait wait wait. How did you go from Rupees to Dollars?

[@ArtinTheBeast]

ahgflyguy magic.

[@taragnor]

The sum of the balance column is meaningless. I mean just consider if you start spending the money a $1 at a time. The balance sum would be massive. But that sum doesn't really equate to any useful information. It could be zero if you spend all the money instantly, and it could be massive if you spend the money in 1 cent increments. This is hardly a tough riddle. It's just finding a weird coincidence where the number is one off, and pretending like the sum of the balances relates to something real.

[@blyat1]

I explained my friends the same way by spending 1yen each time will sum up 50 yen in spent while balance will sum up to (49"50)/2

[@loffel1700]

Exactly. I was like "why are we adding up the balances? Those are arbitrary ending points based on the amount spent" That's like adding up all the mile markers as you pass them while travelling along a highway. That doesn't equate to miles traveled. It does, however, demonstrate a cumulative sum :P.

[@tatianadelgado4867]

Exactly it is not a difficult riddle it's just smt that demonstrates how gullible ppl can be. If you act like the two columns have smt to do with each other and with the total amount of money they will believe they should both add to fifty without even questioning why they should.

[@swinkscalibur8506]

Had the exact same line of thinking

[@TuberTugger]

Another way to look at it, just spend everything on the first transaction. Spent sums to your amount. Balance sums to zero. Seems pretty obvious that the sum of balances is worthless.

[@alok_singh]

This riddle teach us how politicians makes money & common man thinks where is wrong❌

[@kundansand111]

😂😂😂

[@voyageintostars]

abe chomu!

[@Demonblade99]

Sabba Munna , bahut badhiya

[@smartxavier8906]

I am human

[@seenasuresh7639]

@@smartxavier8906 wait are you the real Xavier

[@thelordnaevis4946]

The first thing I said when I saw the thumbnail was “why’d they sum up the balance”

[@simonharris4873]

The real riddle is how this riddle became known as the world's toughest riddle.

[@devendragarwa9238]

Coz it was trending in india🙄

[@Amit-bn5jw]

lol

[@kuldeepdilpat2568]

Well thats a tough one😂

[@Sesquipedalia]

@@devendragarwa9238 just so no one misunderstands, this riddle was trending in India not actually as the "toughest riddle" or somth. The "toughest riddle" part was a joke title to confuse the person who answers it even more. U see when you first see that there is only a difference of 1 and the person says its the "toughest riddle" people tend to look at it in a mathematical and more complicated way instead of looking at the clear picture.

[@KhoiV]

@@Sesquipedalia bruh

[@b303csiu69]

I have $50. First, I spend $1. Balance: $49 Then, I spend $1. Balance: $48 ... Finally, I spend $1. Balance: $0 Yeah, I have $1225. Extra $1175.

[@josepherhardt164]

Exactly. Summing up balances leads to a useless, unrelated figure.

[@iamapoorv4504]

And that is how you become a millionaire

[@TheGrapeApe22]

I have $50. I spend $0, balance is 50. I spend $0 again, balance is 50. I spend $0 again, balance is 50. I spend $0 again, balance is 50. *Total spend: $0. Total balance: 200*

[@Matyj04]

This should be the real way to make money

[@mport7754]

😃😃

[@opsahu8714]

The real riddle is how can someone call this stupidity a riddle.

[@harveyweinsteinslefttit9037]

Exactly lol

[@crimson8043]

Lmao

[@seenasuresh7639]

This is how you become a billionaire Start spending $50 😂😂😂

[@a21imanadhikary83]

😁

[@kateallsop6572]

Still can't understand

[@hariompatel382]

21 din mein paise double 🤣🤣

[@yaseerbeig1356]

Hahahahaa🤣🤣🤣😂😂😂best comment ever

[@thomson7395]

😂😂😂😂

[@arnabroy418]

Underrated comment bro

[@ritikrawat9900]

Haan sbko scheme bta de😂😂

[@btsislife1761]

Aryyy bhai bhai 😂😂😂

[@phatkin]

for me, the key to this problem was realizing that we could insert infinitely many rows where the amount spent is 0, but the remaining balance remains constant. So the number in the bottom right could actually be arbitrarily large.

[@blocksource4192]

I am glad I could figure one of them out finally. While looking at it I realized that the Balance doesn't mean it's the amount you have, it means that's the amount you have left over at that point, meaning you could spend $1 each time, and have 49, 48, 47, 46 and boom, you have $100+ balance while you originally had $50.

[@anshulbishnoi2812]

Well you solved the wrong interpretation of the riddle friend. The real riddle is something else.I have commented it. Try it if you can find it.

[@jefrillahjebaseelan5532]

The fact that I came to know abt this problem a few years back and my father solved it real soon and the worst part is I didn't get it that time 🙄. I'm proud that I have my father is intelligent but sad that I'm not 🚶🚶🚶

[@diamondruby..]

The thing is....the balance coloumn is cumulative. So, you can't get equal amount in both the coloumns. In other words...consider that u have balance of 30. Now that you spend 15, u r left with another 15. Now, like shown in the video, we can't sum up the balances of 30+15 because the 30 is already inclusive of the 15. And it's all a matter of numbers we use. Let us take, the second time, out of 30, we spend ₹10. So we r left with ₹20. So, if we add the balance, it itself gives ₹50. So yeah...the balance coloumn has cumulative amounts. We cannot further sum it up. U r also a genius now😃

[@reda.kharoubi]

looks like Presh is going through puberty again

[@minecraftworld5684]

Exactly👍😂

[@minecraftworld5684]

His voice has deepened

[@stereolifestyle2637]

his voice gradually soften as he say the numbers

[@neetubafna9547]

😁

[@wizzlanderhh2522]

whhat??

[@mikemanh]

Spend 1 balance 49 Spend 1 balance 48.. Go down till 0 Sum of spending 50 Sum of balance 1225 Where did the extra 1175 come from?

[@cubicardi8011]

EXPLAIN THAT ATHEISTS

[@batra204]

This riddle only work when sum of balance is close to the total amount.

[@MrSharkFIN]

You can just do Spend 0$ Balance 50$ Repeat that a million times 50 000 000 Balance

[@draptona]

I spend 1 balance 499 I spend 2 balace 497 Where did thewhere did the extra 996 came from?

[@zohakhan7402]

You can get rich now

[@oliviadbritto]

Hats off to the legends who understood by watching the video!! Because I m more confused😵😵

[@WallysVoid]

Same lmao

[@diamondruby..]

It's simple dude...they just tried to deceive us. But the concept is simple

[@diamondruby..]

The thing is....the balance coloumn is cumulative. So, you can't get equal amount in both the coloumns. In other words...consider that u have balance of 30. Now that you spend 15, u r left with another 15. Now, like shown in the video, we can't sum up the balances of 30+15 because the 30 is already inclusive of the 15. And it's all a matter of numbers we use. Let us take, the second time, out of 30, we spend ₹10. So we r left with ₹20. So, if we add the balance, it itself gives ₹50. So yeah...the balance coloumn has cumulative amounts. We cannot further sum it up

[@kamtakumarthakur7073]

I understand basically when I was child I face difficult y in subratraction and this problem is in this viedo

[@manojmohan9893]

I think I had a better understanding of the problem before I watched this video. After watching it I am bit confused. What was he trying to explain, anyway?

[@KiranPawar-cj3po]

Suppose you have 100 rupees and you spent 10 rupees and again spent 10 rupees and your balance is total 170

[@HappyNBoy]

I think the clearer way to explain this is to just make the early numbers in the spend column smaller. Say 1, 1, 1, 47. Then it's extremely clear that you wouldn't expect the columns to have the same total. 49 +48 +47 + 0 is obviously not going to total to anything tantalizingly close to 50, but also is very intuitively correct.

[@nitinlaheri8968]

1 Rupiya Kaat Over Explaining Ka And Then Your Sum Is Solved🔥😂

[@seemagirme9558]

Are bhai 😂😂😂😂

[@aniruddhmishra476]

Bhai bhai bhai 🤣🤣🤣🤣

[@anybody1154]

Lol

[@mrsen260]

Ye badhiya tha guru

[@lilstarshita]

50 kaat le😂

[@Vrenny]

Let's say you start with $50, and spend $10, you have $40 remaining. You spend another $10, now you have $30 remaining. Adding those two remaining numbers gives you $70. You quickly realize that the "sum of the remainder" doesn't have anything to do with the balance spent. It's much easier to see with different numbers, the trick of the original question is because they end up so close, you're conned into thinking that the sum of your balances (which isn't something you would ever do in real life) is wrong because it seems like it should also be 50 but you've made an error somewhere and somehow ended up with $51.

[@shreyangupta9267]

Actual money is always not equal to remaining money , this is fact and no one can prove.

[@aymanaoufi1615]

Why your voice sounds different at first

[@mrsamsun912]

Ikr

[@whozz]

He was struggling to not laugh at the stupidity of the people who couldn't solve the problem

[@wschmrdr]

Almost like he slowed it down. Or he's about to sneeze.

[@ricardo.mazeto]

He probably recorded just after waking up.

[@dolevgo8535]

i mean.. its the *toughest* question

[@bstyle82]

A trick from my father I fell for as a kid: Both hands have 10 fingers in total. count backward from 10 to 6 on your first hand. Then add 6 plus the five remaining fingers from your other hand. It made me think he has eleven fingers. 😂

[@Demonblade99]

I fell for it too😂

[@ryanleung6753]

What the

[@Bhuvan_MS]

Lol

[@arubbathari53]

Jabs

[@number7417]

I fell for this trick too but dif vers. Another example would be the LOST PESO So I have 100.00 and bought a shirt worth P 97.00 I borrowed money 50.00 to my mom 50.00 to my dad I have 3.00 change from the store and parted each to my mom, dad and my self So I only owe my Mom: 49.00 Dad: 49.00 If I add 49.00+49.00= 98 98.00 + 1.00 from my change 98+1= 99.00 So where's the 1 peso?

[@lordloss4584]

It’s really simple if you also take into account the start, 0 spend and 50 balance. Add it all of then and the spend will still be 50 while the balance is 101. The balance is not relevant,.

[@ennlee8483]

Two years ago , my uncle asked me this question and I cannot figure out why extra one and I kept thinking about it all over a night and now I know why😅😅

[@TomDeFazio]

This is really a variation of the hotel problem that went around a long time ago. "3 men go into a hotel. The man behind the desk says a room is $30 so each man pays $10 and goes to the room. A while later the man behind the desk realized the room was only $25 so he sent the bellboy to the 3 guys' room with $5. On the way the bellboy couldn't figure out how to split $5 evenly between 3 men, so he gave each man a $1 and kept the other $2 for himself. This meant that the 3 men each paid $9 for the room, which is a total of $27 add the $2 that the bellboy kept = $29. Where is the other dollar?" What makes the problem deceptive is that the 2 figures are so close that it plays tricks with the mind!

[@DrHades]

Yeah, I immediately thought about this problem too, it is a much better version...

[@fz3806]

Damn I can’t get my head around this one

[@daffaagung]

The trick here is, why would you add the bellboy's money with the $27 when the $27 ALREADY includes the $2? Basically, $27 = $25+$2 am i right?

[@MrCunha444]

@@fz3806 The correct checking would be: (10-1)+(10-1)+(10-1) - 2 = $25 (the value of the room is the effective value payed by the men minus the money appropriated by the bellboy.

[@DustinMTaylor]

Frick man I just spent like 10 minutes trying to remember this riddle and typed it out in another comment lol. I could've just read the comments

[@hari_g_k_._17]

It has been filmed as a comedy scene with legendary actor Vadivelu in an 80's times of the Tamil Cine Industry in India... It's a very famous one in our region...Finally I got to know it after 5 years now..

[@sheetal7571]

😂

[@aishwaryar1998]

Which movie bro?

[@ricobrawlstars4880]

What's the name of the movie?

[@ramprasad_v]

You can find it by searching "Vadivelu koli comedy" in KZbin. Movie name - Rasaya

[@aishwaryar1998]

@@ramprasad_v Tnx bro

[@mattcook4401]

For someone who doesn’t immediately or eventually understand how absurd it is to sum the balance column, it must be extremely puzzling wondering where the extra 1 came from.

[@Nikioko]

I have 100 €. I spend 1 €, so I have 99 € in the balance column. I spend another 1€, so I have 98 € in the balance column. If I add that up, I get 197 €.

[@user-df4zw7yb4v]

Why is the "World's toughest riddle" the only riddle i've solved on this channel...

[@rmsgrey]

Because naming is done by the marketing department...

[@TheGamer2554_]

Because it actually isn’t the hardest riddle

[@fos1451]

No Name it’s not the hardest it’s the toughest

[@chrisg3030]

Maybe Presh means as long as you persist in thinking the two columns should add up the same, then you couldn't have a tougher problem on your hands explaining why they don't.

[@phantomlogic6940]

I was more confused about why these two columns would be compared like that, especially since the sum of the balance column is irrelevant. The most important information in that column is simply what remain after each transaction.

[@brainboy7123]

Me: don’t sum the balance, don’t sum the balance Them: sums the balance Me: aaaaaaaaaaaaa

[@anubhavhamal3752]

I was asked this question by my grandpa when he was playing cards (called marriage ) the equation of money didn’t satisfied players so he asked about it . I think this surely is one of the most trickiest real life math riddle

[@masterrubic715]

In my real life, that 1$ come from taxation.

[@anshtiwari1593]

Lol

[@minecraftworld5684]

Different from all but congratulations

[@rishiyaswanth]

GST😂 in india

[@Akhilesh_Awakash]

No, Indian's That 1💲goes to GST 🤣🤣🤣😂😂😂

[@dragon5776]

Itd be closer to 50 dollars for me

[@nolahmedi5419]

- where did tha extra rupee come from - probably taxes

[@harshbhoir6401]

Hilarious 😆

[@a_rasik]

GST

[@EdwardCurrent]

If people added up the numbers in their bank account's balance column, they'd find that they "have" a lot more money than they thought

[@krishnabanerjee6573]

The best way to do this riddle will be to do it practically 🙃

[@kimmovillacorta7677]

Another simple situation is if you spend 50 at one time. You will have zero balance. Thus you cannot expect the spent money to equate with the sum of balances

[@masrock9203]

Does his voice seem deeper in this video to anyone else? Or are my headphones just being weird

[@Tehom1]

I got that impression too.

[@ahmedwanas9485]

Yeah me too 😂

[@ricardo.mazeto]

He probably recorded just after waking up.

[@dolevgo8535]

*toughest* question

[@RedSunFX]

I first thought that he has a cold.

[@CrescendoAmpio]

The "balance column" is also called a "cumulative sum", which helps explain why summing it is nonsense - each number in the series is ALREADY a sum.

[@prateekjaiswal8045]

we can also explain them in a way like if we spend 1 rupee each day till 50 days total spent would be 50 but total balance would be 49+48+47 .+.+ till 0 which is equivalent to 1225 This riddle is just to make us confuse

[@ryanhaart]

Huh? I paused at the "riddle" and haven't watched the "solution", but where is the "riddle" here? Summing up the balances has nothing to do with the amount of money. What if I spend 1, then I have a balance of 49, then spend another 1, I have a balance of 48, and so on. If I sum up the balances, I get 1225. Where did the extra 1175 come from?

[@daffaagung]

Ohh so smart aren't you?

[@eventhisidistaken]

What makes it a riddle, is that the sum is close to 50, and fools those who aren't thinking carefully into thinking that it *should* be 50. This is how most riddles work - they set something up that leads your brain to use intuition when you should not. They're similar to jokes in that the set up of the joke leads you to expect something different than the punch line.

[@chrisg3030]

ryanhaart I experimented with your approach as well, but stopped after just two spends of 1 to get an apparent extra 47 which seemed absurd enough. I also considered: spend 1, balance 49; spend 49, balance 0. Total spend 50, total balance 49. So this time the question becomes where did the missing rupee (or whatever) go? This could be the simplest possible variant of the famous missing dollar riddle, which Wikipedia covers together with Presh's problem in the same article.

[@PauIdenino]

ArEn'T yOu A sMaRt OnE!

[@jeremyanderson3819]

It's the classic "here's a graph" scam. Notice how they put the whole "start with 50$" on the side, when clearly the balance should start with 50. Pay attention to what number the graphs on the news start and end at.

[@douggief1367]

Proof you have *11 fingers* ... On left hand 10-9-8-7-6 On right hand 7-8-9-10-11 There, 11. And about as meaningful as the 51 balance.

[@aviralagarwal2369]

Omg. Where did the extra 1 finger came from. Haha don’t think I am nub. I know you have an extra finger.

[@wanghanonymous4348]

Simple Am hrithik roshan

[@manjuranigp.9290]

Where is 6 in right If there is six in left there should be 6 in right too!!

[@douggief1367]

@@manjuranigp.9290 Yeah it doesn't make sense. It's just a joke. 🥰

[@nirmalraj8739]

Vivek comedy

[@CarlWithACamera]

I spend 1, I have 49 left I spend 1, I have 48 left I spend 1,I have 47 left Why would anyone expect the right column to add up to the starting number? That’s not a riddle, it’s insanity.

[@ash0x7]

We don't have to count balance for finding initial sum , we have to count sum of spends For example : - if u have 100 rupee and you spent 99 rupee balance is 1 rupee Now if u count balance it will show 1 rupee that is not equal to 100 It's LOL 😂

[@COZYTW]

Funny enough, a colleague dropped this question to me last Friday and I used set theory to solve it. I illustrated how A' + (AUB)' + (AUBUC)' is not indicative of the universal set because you're recounting the area for the balance. A' has portions that intersect with (AUB)' and (AUBUC)' so it's double-counting the same area again and again. To illustrate this discrepancy, I went with a variation of the question that shows how absurd the summation of the "balance" can be. "I have 10,000 dollars. 1) I spend 300, left with 9700. 2) I spend 600, left with 9100. (notice how the balance's sum already exceeds the original number we had) 3) I spend 1200, left with 7900. 4) I spend 2400, left with 5500. 5) I spend 4800, left with 700. 6) I spend 700, left with 0. Summation of the amount spent: 10,000 dollars. Summation of the "balance": 32,900 dollars. (extreme sarcasm) Oh, where did my 22,900 dollars come from? Could there be a hacker spending my money for me?" I like how the question's choice made it such that people automatically associate a perfect symmetry between expenditure and balance.

[@vuedanto8576]

I have a billion dollare 1) Spent 0, balance one billion 2) spent 0, balance one billion 3) spent billion, blance 0 Total balance = 2 billion Where did that extra billion come from?

[@rcb3921]

A better riddle for this concept goes like this: Three businessmen visit a city at the same time and decide to share a hotel room. The manager tells the men that the cost of the room is 30 units, so each businessman contributes 10 units and they pay the manager. Once they are in their room, the manager suddenly remembers that he's running a discount and the room should only cost 25 units. He quickly pulls out 5 units from the register and hands it to the bellhop, telling the boy to take the money to the three men. But along the way, the bellhop realizes that he doesn't know how to give 5 units to three men. So, he cleverly pockets two units for himself, and gives one unit back to each businessman. Now, each man has paid 10 units and received one back. So the men were charged (10-1) * 3 = 27 plus the 2 dollars pocketed by the bellhop is 29... but the room cost 30! Where is the missing unit?

[@prince5478]

The answer is The room cost was not actually 30, it was 25 because of discount But businessmens mistakenly given 10+10+10=30 When managar realised, he sent bellhop Bellhop kept 2 units and distributed remaining 3 units to 3 businessmens So the equation became (10-1)+(10-1)+(10-1) that is 9 + 9 + 9 = 27 As we know bellhop kept 2 Units, so again 27 - 2 = 25 Here we got our answer...

[@McCurtainCounty888]

​@@prince5478exactly, people mistakenly add negative numbers

[@C7ZI]

With the boy

[@donovanmahan2901]

and the answer is that the two extra units the bellhop pocketed were counted twice, while the three currency the businessmen received back were not counted. Correcting this, you have the discounted price of 25, plus the two the bellhop pocketed, plus the three that were returned to the businessmen, meaning all 30 [kromer] are accounted for.

[@JamesMc2051]

This is the version I heard years ago.

[@northerndarklight5305]

If you had started with $100, and summed your running balance column, the result would be $351. Running balances - $100, $80, $65, $56, $50. The running balances are not meant to be added together and each figure is valid for its purpose only until the next transaction.

[@kusummehta385]

Indians are at their best in creating difficult questions.

[@adityashaw5114]

@@nextphaser ooh means Indians didn't explained the concept of zero.

[@mrsen260]

@@nextphaser you are one of them

[@sanketshetty9691]

Indians are better in creating questions and Americans are better in solving them (huge difference)

[@kusummehta385]

@@sanketshetty9691 ya so they exist because of us😂

[@sanketshetty9691]

@@kusummehta385 no matter who asked questions and who solved questions... No matter how silly the question is the solver will be the superior amongst the asker...

[@anshu1975]

Kind of same thing happens when I try to calculate my marks after exam . I find less marks according to the questions I have done and more marks according to the questions I have left.

[@AnuragYadav-mr2xv]

Becuz you are indian

[@kartikagrawal4354]

@@AnuragYadav-mr2xv chup be lodu

[@marilynhaughton1955]

Yes, well that explanation was as clear as mud.

[@TheRandomSpectrum]

jajajajakajakakakakakakakaksksjajajkakkakakaka

[@ojasdeshpande7296]

Rip

[@JeffDeath99]

It's because sum of spending has no correlation to sum of balance and there's no reason to compare or even sum up a balance log, let's say all you have is $50, Spend 5/Balance 45, Spend 10/Balance 35, the balance summary is already at $80, it's just a trick question overall, the 1 difference in his makes it seem like it's not supposed to be there but in reality who cares sum of balance isn't a thing

[@JeffDeath99]

In other words if you add up what you spend itll always be what you had to spend, and you shouldn't add up balances its just how much you have at a certain time, and if he would of spent the 50 differently he would have a way different sum of balance.

[@HassanAhmed-rf9xr]

@@JeffDeath99 nice explanation. I had actually saw this vid a few months ago but came back an thought well I became smarter maybe I should try again. Sadly no luck an thought is their a trick cos there seems to be nothing wrong 😑.

[@insertphrasehere15]

I quickly realised that the balance column makes no sense. If you spend exactly half then they will be equal, but each time you spend less than half the balance column will grow higher than the spend, and vice versa if you spend more than half. The only trick here is that the numbers have been carefully manipulated to almost equal each other.

[@somrinzi]

The moral: Your balance increases each time you are miser! 😂

[@theprincechandrayan]

It's only a silly question. One should add the money spent.

[@adapateja8618]

Nut one should subtract from total balance amount

[@peterformaini7723]

My first question was, “What does one colum have to do with the other! Why WOULD they be equal?” Good to see my common sense is functioning correctly. Love your videos!!

[@mariolemos8329]

Because it would be satisfying 😂😂

[@swastikadebie3721]

Absolutely right.

[@m.vivek777]

The spent money is original money(starting position 50₹) we are having on which we are doing calculation, while balance money is not having any base itself(don't have starting value) it's derived value from spent money. This can be illustrated with an example of ruler whose value starts with 0 & this puzzle can be solved.

[@alphacat9663]

The fact that I answered it before opening the video (on the thumbnail) 👏👏 for me

[@logiciananimal]

Reminds me of the old "I have 11 fingers" trick, in addition to the "hotel puzzle" some discuss below.

[@LONEWOLFAOW3]

Lol, he didn't even explained why there's an extra money.... The trick is that, when you're spending, you're counting 1-50 but when you're putting on the balance chart, you're counting from 50-0... So , if you do the counting, that extra money is hidden in 0-1...

[@arun-yl4sb]

So they call this world's toughest...😂🤣😆

[@vishweshwarbhat6764]

And now this has exactly 51 likes lol

[@catchatt]

151 likes

[@slouchysenpai1970]

181 😂😂😂

[@theoneinyou2233]

Amanda raasa...

[@umashrivastava3151]

Who they?

[@pub7496]

The difference between the Rupees in the Spent and Balance columns is that a spent Rupee gets counted in the Spent Total only once, whereas a Balance Rupee gets repeatedly counted in the Balance Total until it is spent. So the answer to the puzzle is recognizing that it is not meaningful to sum the Balance Rupees.

[@Siddharth_Tanwar]

I figured it out in the begging. I was thinking why the sum of the balance should be equal to ₹50. At the end it turns out that summing balance has no point.

[@gabrielfranciscorp]

I think the trick behind this is that, in the column ‘balance’, each time the value shifts, you are counting it's value twice. For instance, 30 + 15 = 45, but you only spent 35, and therefore the balance should be 15 total. Meaning, the sum of the ‘balance’ lines simply isn't done to determine the total spent, since every line on balance column is the start money minus the total spent. If you add them up you'll have the start money times how many times you made an expense minus how much each spent cost you, which are two whole different variables.

[@MarieAnne.]

Not only that, but if you spend 10 different times, sum of balances will start with 10 times original balance, and from this you subtract 1st amount spent 10 times, then you subtract 2nd amount spent 9 times, etc... until you get to the end and subtract last amount spent once. It's useless information.

[@tanvirsingh5506]

After watching the video I still don’t get it 💀

[@felixlaurin1310]

I may be a year too late, but basically, the balance column is the remaining result of the subtraction of your current balance minus the amount you spent, which means the sum of your previous balance amounts doesn't mean anything to the amount you've actually spent. I.e: Lets say you always spend the same amount of money each transactions, it'll go like this: Spent(0) | Balance(50) 10 | 40 (50-10) 10 | 30 (40-10) 10 | 20 (30-10) 10 | 10 (20-10) 10 | 0 (10-10) _______________________ 50 (10*5)| 100(10+20+30+40) It's just that the riddle is constructed in such a way that the sum of the balance column is really close to the value of the sum of the column spent, which causes confusion makes us believe there is a close link between the 2 sums when there isn't.

[@all-four-inches]

@@felixlaurin1310 you actually the video did a very bad job of explaining this riddle. You did it much better.

[@anikethsai8055]

Basically, the two sums are not connected in any way

[@aaronbredon2948]

The only relation the Balance column has is balance(transaction) = balance(prior) - spent(transaction) The last figure in the Balance column is what should be put at the bottom, NOT the sum. The correct bottom row is Spend:50 Balance:0

[@olivervarro108]

There is just no need to add up the balance. Let's say you spend 1 dollar. You're balance is 49. You spend another dollar your balance is 48. If you add 49+48 you will get 97. See? There's no need to add these numbers up. It makes no sense to do so

[@Riteshkrpanda]

It is really a very popular Riddle with minor changes here and there and I explained it with through explaining how Liability works but no one understood 😄

[@mayorb3366]

Similar puzzle... Three men check into an inn for the night. The desk clerk charges them $30 for the room, and each man gives him $10. After the men go to the room, the clerk realizes that there was a discount he did not apply. The room was actually $25. So he gives 5 one dollar bills to the bellhop and tells him to give the money to the men. The bellhop can't figure how to split the money 3 ways, so he just gives each man $1 and keeps the other $2 for himself. So each man actually paid $9 for a total of $27, and the bellhop has $2, for a total of $29; Where did the other dollar go?

[@PapaMike23]

Just spend 0€ one million times and you have 50.000.000 €. Or in other terms: Phase 1: Spend no money (and collect underpants) Phase 2: ?? Phase 3: Profit!

[@georgesos]

That's the best comment ever!and it doubles as a profit making scheme

[@dhy5342]

Good One!

[@sporksto4372]

Wow, I really like this comment.

[@ridwansetiadi8393]

*insert meme: stonks

[@chrisg3030]

Jock: What are you running behind that bus for? McTavish: To save myself £5. Jock: Why don't you do what I do and run behind a taxi and save 25.

[@carolinfardal]

This feels like the missing dollar riddle but a million times more transparent about the fact that you're doing the wrong computation, the fact that anyone gets tripped up over this for more than a second shows how many people view math as just some magical black box that gives you the answer if you do the right ritual

[@wariolandgoldpiramid]

Well, I am decent at math. I didn't immedietly, at a first glance, see what happens. But, as soon as I started analyzing the right column... "Okay, 30+15 is 45. But why are we adding these?".

[@carolinfardal]

wariolandgoldpiramid That's why I said "for more than a second." I absolutely agree that it feels confusing at a first glance, as I felt that way as well, but something like this is able to go viral, people are presumably having arguments about it, when anyone who's remotely fluent in even the basics of mathematical thinking should be able to notice the problem quickly

[@wariolandgoldpiramid]

@@carolinfardal how would you compare this to the Monty Hall problem? The solution is very easy to proof, but people keep arguing about it.

[@carolinfardal]

wariolandgoldpiramid I feel like the Monty Hall problem is a more "genuine" paradox than this is, this is only really confusing if you blindly accept that the balance should add to anything significant, which isn't really reasonable if you take a moment to think about it. The Monty Hall problem though, sets up a problem where even mathematicians trained in probability can reasonably think that either side is the same - after all, they both might or might not have a car behind them. But, if you take a more careful, principled investigation into it, you can discover for yourself that there is a difference. The difference between them feels like anyone should be able to work out the solution to this by asking yourself some fairly obvious questions, "why should the balance add to anything?" for instance, but Monty Hall doesn't have an obvious answer without plotting out the probabilities carefully and methodically.

[@carolinfardal]

After thinking about it further, to solve the Monty Hall problem you need to be able to create and dissect a probability tree, which isn't something I'd expect the layperson to know how to do necessarily, but to solve this all you need is to be aware of your own assumptions and test them, which is something I'd hope the layperson can do. In fact, it feels like most people can do as much, but many people just shut their brains down when confronting a math problem like this, because they think math's too confusing to be understood and just refuse to even try.

[@armchairtin-kicker503]

According to "How to Solve it" by George Polya, one should consider setting up a similar but simpler problem. I suggest setting up a problem where only 1 rupee is spent at a time, therefore the balances would be 49, 48, 47,...0, and according to Carl Gauss, the sum of the balances would be 1,225 rupees. Yet, the sum of what was spent would still be 50 rupees, suggesting that the two values do not necessarily coincide. And of course, if one spends 50 rupees on the first iteration, the total of the balances is zero rupees, both similar but simpler scenarios making the point.

[@apaarshrivastava]

Person: Have 1000 Rs 100 Used Balance: 900 Used 400 more Balance: 500 Used 500 Balance: 0 Total amount of money used: 100+400+500= 1000 Total of balance:900+500+0= 1400 Logic: Has left the chat and committed suicide.

[@sebthes3727]

(before watching) Spend | Balance 1 | 49 1 | 48 = 2 | 97

[@namelastnamefirst4520]

Exactly. What is the wrong answer here?

[@saurabhpatil9496]

Seb TheS

[@covid-19ultrapromax25]

Change the title of the video, remove "explained" and insert "unsolved". Before I report your video....

[@suryatejasunny]

@Suraj Jha you just replied

[@manishrana6128]

🙄🙄🙄🤣🤣🤣🤣😂😂😂😂😂😅😆😁😁😄😃😀

[@cryozen8003]

@Suraj Jha six actually

[@namansalecha26]

Yes

[@sajadmir3477]

Yes

[@Philip-1]

VISA Support (with Indian accent): Hello Mrs Smith. I'm affraid that the sum of your previous month's balances does not equal the sum of what you spent. Mrs Smith: *_hangs up_*

[@Tehom1]

A good lesson in calculating the right thing.

[@million1828]

Thank you to the comment section i saved my 3 mins of time.

[@SpaceCadet4Jesus]

Reversing the amounts (kinda) gives: Start with 50. Spend 30, balance 20 Spend 10, balance 10 Spend 5, balance 5 Spend 5, balance 0 ----------------------- Spent 50. Spent 35 Balances are remainders, not to be added up.

[@salxrn]

this riddle only works in that setup if i spent all 50 rupees on the first go my balance will be 0. oh no what happened to all my money where did it go?

[@ayubi3642]

Who does accounting like this? 😂

[@matil7880]

me: well you spent 50 and you were still left with 0 at the end so this is shenanigans.

[@Taigan_HSE]

The real trick here is the amounts were carefully chosen to make it come out close. If you start with 10 and subtract 1 each step the flaw is obvious.

[@gimik2593]

I think the reason this would be considered a riddle is due to how it’s setup where’s there’s only 1 missing. With such a small difference, I feel people are more likely to want to explain why the 1 exists rather than go to the obvious answer of summing the balance doesn’t get you the original balance. If the riddle was laid it out like 50 constantly subtracting one, for a balance in like the hundreds, people would be more likely to call out it being bs.

[@monrealis]

Let's say I have 50 euros. Now let's spend 0 euros 100 times :)

[@DD-rl7xo]

Profit! I mean this is what we do in india to make ourselves rich😂

[@chrisg3030]

There's a character in Catch 22 who gets richer and richer from government subsidies for increasing the amount of land he doesn't have under cultivation. Another bit of fun with this kind of idea is "Yesterday upon the stair I met a man who wasn't there. He wasn't there again today, I wish to God he'd go away"

[@NoobGamer-ik4ed]

Someone asked me this. I told him that it is not absurd that the sum of balance is 51 as the sum of remaining balance is not related to the total amount spent. However that smartass didn't understood what I said and simply said I am wrong. Now, you verified my answer. Thank you

[@priyamdey324]

NoobGamer same with me I solved it 6-7 months ago but when I explained it with my classmates they said I m not doing this in the right way

[@samarth3957]

@@priyamdey324 ask them what's the right way. Probably by counting their brain cells.

[@nitinkumar7754]

Bur it says I have only 50 then how can he have 1 rupee remaining after spending his 50

[@BlackPearl27]

I didn't see how that made sense at the start but it being explained to me like this made me understand it pretty well. I guess the difference is I stayed humble and was ready to learn instead of pointing fingers and trying to be right. I hope that guy learns that he doesn't know everything...

[@hwu6402]

It's interesting to ask some day traders who got thousands of transactions in their statements to see just how much the numbers in any balance column could sum up to.

[@justice4scalia846]

I think the guy was married and he didn't spent any of the money. Matter of fact, she saved him over 149.00 on the first purchase alone and now is entitled to half that savings up front.

[@agabe_8989]

3:46 Every time i hear something like that, for example "Now you can try it on your friends". I think about those friends that wouldn't watch these videos. It never worked :(

[@simonboyane1140]

I never felt so inferior regarding my maths skills 😂😂😂😂😂

[@henriksoderstrom6815]

Easier to see the error if you start out with 50 $ and spend 1$ at a time 50 times, then you end up with a balance of 0, while the sum in the right-hand column will be somewhere around 1275$. Then it is pretty obvious that summing up the right-hand column is a pointless exercise.

[@zacharyleonard9413]

I figured out this one easily I think. You could have had the original 50 in the balance column from the start with a placeholder 0 in the spend column if you want and that wouldn't make the table any less valid but your balance total would be 101. This tells me that the balance total doesn't really mean anything.

[@hanyk06]

I have trouble accepting this the "toughest" riddle. It was plainly obvious to anyone with half decent math problem solving logic

[@tonyttt31]

Or anyone who has ever read a bank statement in detail

[@dummyliug]

Yes. My first thought to the question was What the hell is the Sum of Balances?

[@nerimaken482]

Chill, while it may not be the toughest don’t go categorising the ‘anyone’s that could have done it. Different people get stuck on different areas. Doesn’t mean they lack the ability to solve maths problems.

[@ashdoeslife1794]

Me who hasn’t even know how a bank or taxes work

[@rachmadhan23]

I've found the formula for "the extra". The extra is the 3rd spend + 2(the 4th spend) - the 1st spend. If there are 5 expenditures or more, we can add the Xth spend times X-2. For example, we add 3(the 5th spend)😉 Sorry, my English isn't good😅

[@Malefic_Roar]

Nice

[@coolestgedown1versionrobbe647]

1 thing, I have $50, I used $6, then I have $44 left, then I used $30,I have $14 left. The balance is just after you bought the item, not how many money you spent

[@derpay4945]

I guess it takes money to make money. Not only is it an "ImpOSSIBle RiDdlE" but it's also a very life teaching riddle.

[@derpygolem5319]

I already knew it from the beginning . I only know this because there’s a similar puzzle like this but instead there is a missing dollar