"UNSOLVABLE" Logic Puzzle: What Are Their Ages?
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- Опубликовано: 21 окт 2024
- This is one of those brain teasers that sounds like it's impossible to solve but you can work through it (like the logic puzzle of Cheryl's birthday). A mathematician tells a census taker he has 3 children. The product of their ages is 72 and the sum of their ages is the house number. The census taker tries to figure it out but explains he still does not know. The mathematician says, "Of course not. I forgot to tell you my oldest child loves chocolate chip cookies." Now the census taker figures it out. What are the ages of the children?
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The correct answer is: 1,1,72 of course
I'm 72 and my dad is a 40 year old mathematician :D
+Heliocentric But this is the only combination that gives the house number 74, and the census-taker would have guessed without the extra detail about chocolate cookies.
+id523 I disagree. If that were the correct answer the census taker would assume the mathematician made a mistake long before assuming he adopted a 72- year old (which is the most likely of the various unlikely possible scenarios).
OMFG 72 LIKES
+Heliocentric either the most sexually active...or least sexually active man on earth
The census taker stares at the mathematician and says "I don't have time for this nonsense. Just tell me."
Very true to life there.
No you have to guess
@PuraguCryostato That escalated very quickly
That's every student who has ever asked a question to their math professors.
@@jamesmayle4712 uhuh
I thought the answer was 288 and 1/2 and 1/2
+Patient Because that adds up to 72
+Falax Scavenger it MULTIPLIES to 72, doesn't have to add to
+Patient Zero I hope I can still eat cookies when I am 288.
+PlasteredDragon I'm sure there's a way
Omg lawl
Census taker: "What are the ages of your children"
Mathematician: "solve this riddle"
Census taker: "here’s your court date for obstruction of the census"
Mathematician:
:(
🤣
That’s so funny
"The product of my children's ages is 72 and the sum of their ages is my house number,"
"Sir this is a Wendy's"
😂😂
Reference to the show that will remain unnamed?
😂😂
🤣
“Larry, I’m on DuckTales.”
i got it! Before watching the video.
The mathematician has 3 kids the oldest one likes chocolate chip cookies. This means that the oldest child is a pleb and can't be older than 9. No one has 3 children when they realize that the first one is a filthy casual. This means that during the second pregnancy he decided not to have anymore children. So why then does he have 3 kids? Well the answer is simple, he had twins!
On average it takes around 5 years to notice just how plebish your son or daughter has turned out. so the difference between the twins and the eldest child is 5.
this means that the possible combinations are:
1, 1, 6
2, 2, 7
3, 3, 8
or
4, 4, 9
the only combination there that multiplies to 72 is 3, 3, 8
meaning that the guys house number is 14. and the age of his 3 children are
3 3 and 8.
Wow he solved it weird but whatever, same answer. ezpz lemon sqz
My solution was 6,4,3 and the house number is 13
3×4=12 12×6=72
+Jamal McElroy yeah, but after he got all the possible combos he said he still couldn't figure it out (because there was 2 identical answers...that is 14). that's why the house number had to be 14. and the last piece of info about the eldest kid came in.
+Shameema Bhyat Thanks! But I already knew. I just wanted to say I was wrong😂😂😂
+Jamal McElroy hehe , apologies Jamal ;-)
Maybe he said he couldn't figure it out because he didn't feel like spending ten minutes working out all the possibilities as opposed to telling the mathematician to just give him the damn answer.
there's only 3 possibilities from his perspective :p
Well, I took 1 minute to figure it out so... yeah
@@fuseteam Given that he knows the house number, I'd say there is only one possibility, from his perspective.
@@happinesstan ehhhh?
@@fuseteam I wasn't considering twins. I mean I was. I just ignored myself when making this comment as I couldn't be bothered to work it out for twins.
How it really went:
Census taker: "What are the ages of your children?"
Mathematician: "The product of their ages is 72, while their sum is the house number."
Census taker: "How am I supposed to get that?"
Mathematician: "Oh, I'm sorry, I forgot: my oldest child likes chocolate cookies."
Census taker: "Yeah, okay, I got it now." writes down 1,2,3 "Ain't nobody got time for this."
Yess 😂😭
or just asks the kids. 🤣🤣🤣🤣
The answer is 648, 1/27, 3, and the house number is approximately 651.037
that's a bit old for someone to still like chocolate chip cookies, don't you think?
@@YSFmemories at that age they start liking them again. Or so I heard
the only correct answer
The kids are 4, 5-√7 and 5+√7. House number is still 14... 😁
I once tried testing a census taker with this riddle. He ate my liver with some fava beans and a nice Chianti.
My regards to the good doctor.
It’s so annoying when that happens. I don’t know how many livers I’ve lost this way.
*slurp slurp slurp*
That's creepy
@@pzcat227Good evening, r/woooooosh
Census taker: ages?
Mathematician: here's a riddle for ya, son
Census taker: just shut the f up i ain't got no time
As a Math professor, this is EXACTLY what I would feel if I was the census taker.
@@e2theeyepie I think it's really cool to be working as a math professor, isn't it?
Would be me😁
Well... I mean, congrats to everyone who did figure it out. But the whole concept of one child being the oldest means no other child can be the same age is a huge stretch. You can't definitively say no parent doesn't refer to an older twin as "the oldest", and absolutely any parent would refer to a child 9 months older than another as "the oldest". So... it's still completely possible that the answer is 2, 6, 6, and the father was just hoping the census guy knew a good cookie recipe.
Especially if the mathematician specialises in Chaos Theory - butterflies wings are nothing compared to the duration of labour
On pair of twins I knew were very specific about who was older.
my solution was 9,4, and 2... assuming no twins (so no 6,6 or 3,3) and nobody was born directly after one another (no 9,8,1)
@@Daikael 9,4,2 doesn't work. There would be no need for another clue if the ages added up to 15.
I think you're kind of person who looks for dirt under nails. General knowledge agrees against your reasoning so the answer is that. Also, disagreeing a general knowledge doesn't make anyone an interesting person, rather a weird person.
@Shananananon You are completely right but the thing with the ages doesn't really matter since the mathematician wanted to create a creative unique answer. If one of the 6 year olds could be referred to be the oldest, then the answer wouldn't be unique anymore. Another argument could be that the census wouldn't get any new information of the word "oldest" if "2, 6, 6" is a possible answer. I'd say that the info "mathematician" is crucial.
1. Intake riddle.
2. Ponder riddle.
3. Get frustrated.
4. Unpause video.
5. After 5 seconds, suddenly realize a vital piece of info, just before it's said in the video.
6. Continue solving.
7. Hit another roadblock.
8. Move mouse cursor over unpause button.
9. Get another burst of inspiration and solve the riddle.
10. Write comment detailing method taken to solve riddle.
***** Oh yes. Apologies.
+Hermi Monk ahahahahah
11. Go eat chocolate chip cookies.
Here I was overthinking it from the thumbnail:
What's the house number? IDK
What's the oldest son loving chocolate chip cookies have to do with anything? IDK
The writers want me to do some lateral thinking with the way this is written I bet!
Are there any notable cookie eaters that I know their address?
Oh what! There actually is! The cookie monster lives at 123 Sesame St.
So if their ages are A, B, and C then:
A+B +C = 123
ABC = 72
Plug those into wolfram. Glad I didn't spend 2 pages solving that by hand. Whew!
A real solution exists!
Their ages must be 69.3362, 1.3319, 1.3319!
Is it just true that cookie monster is the oldest one on Sesame St?
I don't know they all seem to be different species from one another!?
Maybe they experience time differently and this is a "dog years" sort of age keeping.
Still kind of weird to think that the cookie monster would be that much older. I mean that's a huge delta between 69.3362 and 1.3319.
Is this consistent with Sesame St. canon?
This is a much better solution than the one given in the video, lol.
Your solution would work for ABC = 123 and A+B+C = 72
Wolfram doesn't know how to do simple multiplication.
@@jondolar64 Apparently I don't know how to input and am not diligent enough :P
The actual answer is that no real solutions exist
However:
A≈121.46 + 1.42109×10^-14 i, B≈0.769927 - 7.10543×10^-15 i, C≈0.769927 - 7.10543×10^-15 i
is a only solution who's real components imply an oldest child. And you know, maybe it makes sense that the sesame street cast has an imaginary component to their age since they're imaginary characters...
The problem is, Cookie Monster's age has never been officially revealed, so this puzzle isn't actually possible.
census taker: how old are your kids?
math nerd: here's a riddle that'll answer that.
census taker: sir i have a thousand houses to get to, i'm just gonna put down that you have three cats.
you f*cked up my screen
I like cookies, guess my age
4?
8?
29? lol
Potato and half a tomato
13
What person has twins at 1 and a 72 year old son or daughter
Me
dirty dirty centenarians (or people close to)
the Japanese
Someone older than 72.
John Smith "That thought is rediculous," is the most harmful concept in all of science. Open your mind to every possibility, or you will never discover anything.
You forgot to mention that the census taker is a perfect logician. Or are we just meant to assume that detail?
Nothing indicates he is a perfect logician. But the video certainly does indicate he is smart enough to figure it out as it clearly says he did figure it out. Did you miss that?
@@52gt Well whatever, the question and answer provided here both have problems. Put another way, they're both critically flawed.
No you’d have to include he’s an imperfect logician or else he would have gotten it when he had the two combinations left. This riddle blows.
@@davidporter671 Why do you say he would have gotten it then?
@@waynelin6238 Nvm I had the order of everything wrong.
I thought this was going to be a pun based on the chocolate chip cookie detail... because one eight nine of them....
Dad Jokes > Math.
I like your reasoning lots better than the "correct" answer!!
LOL
"Groan joke". Love it.
Often joke answers annoy me but this is gold :D
This is the one. The truly correct answer 😭
I can imagine the obsesive mathematician talking to his wife:
"ok dear, in 9 years time there will be a census. we need to have a child by next year and then twins in 6 years time. be aware that if we don't have twins I will have to seek a second woman to have my child/ren, so they all have the right age"
No need to find another woman, just conceive another child in 9 months, simple!
But they lived in an apartment, so they had to find a house as well (one not in Reseda or the math wouldn't work).
Long before youtube it was "36" instead of "72", and his oldest daughter playing the piano....
exactly what I thought ;D
I read it first in the compuserve magazine... back in the days.
Hassan Ali Husseini i remember
Well, having a 72 year old child and 2 one year old children, his mind is probably mostly gone anyway.
@ OC: That would make so much more sense.
I think there is a better explanation of why the cookies information is not ambiguous. The mathematician says "of course", so he realises where the census taker has arrived in his deductions (house number 14, ages 2/6/6 or 3/3/8). It follows logically that he then gives the census taker enough information to solve the problem, otherwise he would have said some other clue! If his two eldest children were the same age, his given clue would be ambiguous at best and misleading at worst - so he would have to use a different clue in this case. Thus we can exclude the possibility that the two eldest children are the same age.
+codebeard that does make more sense. thanks.
+codebeard It's not conclusive though. There's nothing to prove that the census taker isn't stupid. 1/1/72 fills all of the given criteria, as do 2/4/9. Anything beyond that is implied at best, and implications are irrelevant.
For the Hunt it would only have to be implied if they had not said "of course!"
+For the Hunt
There's a convention that's usually explicitly stated, but sometimes simply implied, that in logic puzzles like this, all parties are infinitely logical, meaning that if there is a correct logical or mathematical solution, they will take it.
@For the Hunt. In which case the house number would of been 74. Their is only one way to get 74. So their is no need for the additional clue.
A census worker could not solve this problem...
😂
I was a census worker and not one person gave me a smart-ass answer like the one in this puzzle. If they had, and I wasn't amenable to the mathematician, I would simply acknowledge that the respondent neglected to give an answer and instead posed a math-teaser, and they could be liable for a fine for a hundred dollars. Unfortunately, since the government hasn't prosecuted non-response since 1970, the mathematician would likely get off this time.
Exactly.
Census workers are typically hired once every five or ten years from the ranks of the otherwise unemployed on the basis that; a) they can write legibly, b) can approximate a clean & tidy person, and c) can walk a few dozen blocks a day.
They're not hired for their mathematical prowess or cookie counting skills.
The mathematician was lucky to avoid a smack in the mouth.
I refuse to give census info.
Really. So lets hire you because you think it is OK to smack smart asses in the mouth.
I hope you come to my door. After I dispatch of you for smacking me I will sue the feds. They have a lot of money.
For this to happen, we have to assume that the mathematician was just bored one day and realized that the sum of his kids' ages was his house number for some reason.
No, he just has to move three times a year.
@@elijahbryce9526 Just twice a year. Remember, he has twins! 😄
This is not an unreasonable assumption, my dad is always thinking about what he can do with our ages to make some kind of interesting insight lol
People notice things like that.
I don't think "generally doesn't happen" is precise enough for a puzzle
100% a logician or mathematician would never accept that. So clearly the census worker just figured "screw this, I'll make something up".
Even among twins of the same age, one is still described as "older" if they were born first. So it could be the other answer.
Also, I picked 1,1,72 because it's hilarious.
The mathematician is trying to give the census taker enough information to get the correct answer. Calling one of twins THE oldest would not help in arriving at the solution, so your objection doesn't stand.
Yea thats exeactly how i end up being called to help out more. Im the older twin
Somehow though, in the end my brother ends up helping out more than me😂
Race: elf
How about 1/2, 1/2 and 288?
Imagine the planning necessary to achieve 1, 1, 72.
Sorry, but twins are not usually (if ever) born simultaneously. My guess is that most parents of twins will, on occasion, refer to one or the other as being the elder.
Some are born conjoined
Hiya S.
Of course, thank you.
I'm glad I said _not usually_,
;)
And I guess the mathematician just decided to go a bit easy on the census taker, so therefore oldest would be a distinct age
Good point. The "eldest child" thing was a bit of a stretch -- especially because it was used as the central point of information (to decide it WAS a sum of 14, AND which of the two 14's it was). A bit much.
GetMeThere1 That detail only showed which of the two #14 possibilities was the right one. The fact that the house number is 14 is derived solely from the census taker not knowing the answer based on the first piece of information. Also, even if it is arguable whether there has to be a eldest child, we are told the problem CAN be solved definitely and the assumption that there is an oldest child with a unique age is the only way this is true so based on that detail we can assume this is the case.
.... nah. too much "implied" info
+Adfucker King the eldest requiring a distinct age is a bit far.
+DesmondAltairEzio Not really.
The age didn't need to be 'distinct' in the way Presh described it. (as in whether someone would 'normally' refer to a twin as older or not). The fact that the father mentioned the eldest age means, in itself, it was important to solve the riddle. And it was pretty clear, relevant to the first clues, that once you had a list of possible solutions that had the same sum (the address), that the 'eldest age' info would then identify which sum of the ages was correct. Which is why it's called a clue, it doesn't need to be an emphatic truth.
Ya the oldest cookie thing is retarded
Yep.
"My oldest child likes Chocolate Chip cookies." Is irrelevant, I'm 15 and eat them every single day and they never even stated his house number, I just divided 72 by 3 different numbers and got 6,3, and 4. The solution to this riddle is that the mathematician is an ass.
There is no logical reason to assume two children don't have the same age (born 10 months apart, one is adopted, etc). That's not "controversial", that is a flaw in the puzzle.
There is no reason to assume the census taker is playing along enough to even try to do the math, or skilled enough at math to calculate all sums in his head. When he said "I don't know", he could be saying he is unable to/unwilling to even do the math to play along (this would be more reasonable in real life when someone just wants to do their job)
Just a flawed puzzle. It doesn't test one's logic; it tests if one thinks similarly to the puzzle author.
"....he still does not know ...."
It's incredible that NON-UNIQUENESS (of the Sum) was the clue....did not get that AT ALL
I kind of tuned out when he said, "this usually is the case" describing a LOGIC problem.
He worded his reasoning badly, but the logic in the problem's enunciation is flawless. The mathematician adds the chocolate chip detail only after the censor tried to get an answer but got stuck on the bottleneck of two possible correct ones with the data he has - as he, unlike us, knows the house number -. The mathematician adds that detail fully knowing where the censor got stuck, and the phrasing makes clear that the added detail is meant to provide a definite solution to the riddle, so, if he had two eldest twins or children born during a period inferior to 12 months the added detail would be useless in order to determine the right answer.
I got it, but I'm still frustrated by the idea that someone who is nine months older couldn't be referred to as the 'eldest'. Plus, that children are 'unlikely' to be born close enough to be the age despite two being three in the solution.
+Oliver Payne The younger children can be twins but there must be an oldest one.
I thought this was weird too, it's not a good riddle when you have to change how reality works to make the riddle work...
Harm Prins
How is that?
+LivingChords fair point. However, I think you can agree his second assumption isn't probable. Or at least, it isn't beyond reasonable doubt?
Oliver Payne
You mean the assumption that his two oldest children havent been born in the same year? I find that pretty probable. who gives birth to two children in the same year?
Cool puzzle! I got to the list of possibilities, and then was stumped, because I completely forgot that I could take the census taker's reasoning into account. I love those sort of puzzles, where you have to think about what other people's thoughts mean. The chocolate chip cookies was a funny info burial.
2,4,9
3,3,8
3,4,6
are all very possible. I understand the point about not referring to twins as "my oldest",
but as far as the age difference to like cookies, all these options work.
It's illogical to assume people don't call their twins older or younger or call their children born less then a year apart older or younger. if your 9 months older then your sibling then for 9 months of the year your age is 1 more then your sibling. i actually knew two borthers that were born 10 months apart from each other. they ended up in different grades because one had their birthday just before the school year started and the other had their birthday just before the school year ended.
I said 1,6,12 because 1,6,12 multiplies to 72 and adds to 19. And "Chocolate Chip Cookies" has 19 letters. How is that not right? That's a significant age difference....
Yes you're right. It is a big difference. But remember that the census taker could not figure out the ages even with the first two clues. 1,6,12 is the only combination that adds up to 19. If that was the answer the census taker wouldn't need a second thought. However he was stuck and that could only be because there is 2 or more combos adding up to the house number (which he knows because he's talking with the guy inside his house so he probably saw it outside). Specifically the combos 2,6,6 and 3,3,8 which both add up to 14. Now he's stuck and can't be sure until he gets the third clue that implies that there is an "eldest child". Which in that case the answer is 3,3,8.
erm to be honest.. 'chocolate chip cookies' has 20 letters, damn:D
Well if he couldn't tell that two of the children were of very similar age then I doubt he could tell the house number.... And if the was one who was distinctively older then he would already know what the answer is. So the dude is obviously blind and therefore can't know what the house number is.
C-h-o-c-o-l-a-t-e-c-h-i-p-c-o-o-k-i-e-s I also counted and no, it's not 19 but 20 LETTERS.
Where dos it say he say the children. He did see the house number as that is part of what he needs to know for his job. I think maybe you did not solve this.
Hah! I knew it was 3, 3, 8!!!! Thank you, brain, for not realising there were combinations beside 3x3x8!! 😂
The choco chip cookie clue is not enough to solve the problem. Look, when their ages are same, they can be twins or not. In either case their fathers ,or parents mathematicians or not, can call one of their children, as older than the other. Even if they are twins their parents or between themselves consider that one is older than the other and act or talk like that.
So the answer is unclear. It can be either one of the ages summing 14.
Being the father of twins one is always considered the older, and it is not a factor of birth sequence
+joliettraveler Yes i know. He said that if his children are twins or born in the same year then their parents won't call one older than the other which is not true. so the the answer is unclear. still a good puzzle though : )
The fact you are taking something as simple as singular tense descriptors and attempting to make it WAY more difficult than it is over the semantics of if parents call one twin their eldest or not, when it has NOTHING to do with the problem at hand makes me worried about what kind of responsibilities you are given in your everyday life and workplace.
If you have to create reasons for something to not be solvable by injecting your own non essential nor required factors for the sake of arguing semantics that hold no relevance to the outcome one way or another, then you are probably unemployed, or been in the same stagnant employment position making similar excuses about why after 10 years you are still making min. wage in the mail room when people who have been there less than 2 months get a raise and promoted to supervisor.
Because why see a problem for what it IS, when making up imaginary factors for why YOU cant solve it is so much more fun.
aykm Marcus!! It has EVERYTHING to do with with the problem at hand.1:24 "You wouldn't generally refer to twins as being the oldest child". He said it, no me, but HIM.Which is not true.
And keep your nose to yourself. You know nothing about me. Stop pretending like you do. Why did you say that shit? 'cause you think that I think it is unsolvable? fyi, BRAINBOX, I solved it. I worked it out. You didn't know that I solved it, did you? well you know NOTHING.
+Sohan BENHUR I can see that even with the math being shown to you, you are still too damned stubborn to accept that in this case you are wrong.
You are wayyyyy too hung up on if ppl call one twin the eldest or not. The cencus worker is asking the father, who is a mathematician. Not only that, but you don't get to split hairs over if parents with twins call one the eldest when LOGICALLY when the MATH is worked out, your options end up being 2,6,6 or 3,3,8. The eldest liking choc chip cookies is the clue, because he is basically saying one, I REPEAT, ONE number is higher. He did not say one likes choc chip and one likes oreos, or oatmeal rasin, or anything that would lead you to pick 2,6,6.
The ELDEST loves them. so that is why it is 3,3,8.
The fact that with it all laid out before you, solved, explained, and reiterated numerous times you are still beating a dead horse over if parents GENERALLY call TWINS older to random people is how I can pretty much sum up your overall mentality.
By the way, there are 3 sets of twins in my family. Guess what? When asked how many kids my aunts and uncles have, they say 3, or 4 or 2. i.e. 3, twins who are 16 and our youngest is 13; 4, 2 girls 10 and 12, and twin boys who are 7; 2, our twins who are 15.
Parents dont specify which twin was older unless ASKED, because it really doesnt matter in general conversation, because besides a couple minutes, and in some cases a few hours, some a little longer, THEY ARE THE SAME AGE.
I seriously hope this has made it through the big rock you call your head.
The riddle also works when the product is 36 instead of 72 by the way ;)
(The solution is different, the answer being 2,2,9, but the principle is the same.)
Adding an extra constraint at 1:50 during solving the problem makes this a bad video.
Good puzzle. I like the idea that you have to factor 72 to find prime factors and then find all combinations that give the product of 72. I like the idea that there is only one product that is not unique. I didn't solve it, this time I was too lazy to use the technique "Get your hands dirty". By the way, does the phrase "if you add up the ages of my 3 children" mean that you cannot have more than 3 children?
Who's to say you can't call a twin as the "oldest child?"
Right? I am the oldest and I'm a twin, no one refers to me as anything else but "the oldest child".
You can, but then providing that detail wouldn't have been enough to isolate the correct answer, which is meant to be the case. So, as the fact of singling one song as the eldest is expressly provided as a distinctive, final piece of crucial information, the only possible contextual interpretation is that the highest number in the ecuation is meant to be unique.
It's 2 am here and I'm watching all of this guy's videos.
What am I doing with my life.
Legends say that this guy is still not able to sleep from the past 4 years
I'd say 3, 4, and 6. interpreting that the oldest daughter is younger and not 12 as the other possible solution would suggest (12,2,3). but I guess the guy can see the house number so he would know if the house number is 13 or 17.
The census taker (CT) has one advantage on us. He knows the house number.
Given that the ages are all positive integers, the product of 72 can be achieved (mathematically) in many ways
(some of which can be ruled out as obviously out-of-bounds, but that won't matter):
1 + 1 + 72 = 74
1 + 2 + 36 = 39
1 + 3 + 24 = 28
1 + 4 + 18 = 23
1 + 6 + 12 = 19
1 + 8 + 9 = 18
2 + 2 + 18 = 22
2 + 3 + 12 = 17
2 + 4 + 9 = 15
2 + 6 + 6 = 14
3 + 3 + 8 = 14
3 + 4 + 6 = 13
The ages are 3, 3, 8; the house number is 14.
Any other combo and the CT would be able to get the ages by knowing the house number, because there would be only one way to get it as a sum of 3 +ve integers whose product is 72.
"14" is the only sum that admits more than one way to get those 3 numbers (2 ways in this case).
But then, given that there is an oldest child, the (3, 6, 6) combo can be ruled out, leaving only (3, 3, 8).
**Note: Technically, twins are never exactly the same age; one is always born before the other, usually by mere minutes.
But we're going to ignore that, because that's what mathematicians do in problems of this sort.
Fred
Ignore the "loves chocolate chip cookies". Just worry about "The oldest child". So there is only 1 oldest child with a distinct age.
I made a list of unique combinations and then ruled out the ones where anyone would be 18 or older (because then they're not a child), and put the sums next to them:
72 =
1 x 6 x 12 ; 19
2 x 3 x 12 ; 17
2 x 4 x 9 ; 15
2 x 6 x 6 ; 14
3 x 3 x 8 ; 14
3 x 4 x 6 ; 13
The only way he could be confused about which one it is, is if the house number is 14. And since we know the oldest child has a distinct age, the children must be 3, 3, and 8.
Yay! I did it!
The oldest child cannot by anyway infer automatically that the younger 2 are twins. They could still have distinct younger ages. The solution is fatally flawed by this one language reality.
+TRAKARU ALVAREZ No it isn't. The mathematical parameters of the riddle mean that the above options are the only ones possible.
+TRAKARU ALVAREZ You don't understand. If the house number was 14, he wouldn't know which one it is since two are twins, and there are 2 combinations. If it's not 14 then he could have figured it out without the cookie part.
But house numbers MUST have 3 digits...... waaaaaaaaaaaaaaaa!
^ That one clearly went over my head...
Census was Newton?
Amd here i was thinking "oh, the oldest child is 8, because he ate the chocolate chip cookies".
This was a bonus question in my grade 11 algebra class, only they summed to 13, multiplied to the house number next door and the oldest one had red hair. I like the 'next door' aspect as it adds the extra confusion of, "Well, most house numbers are separated by 2, so...". Completely irrelevant, but leads to some interesting conversations when people are trying to solve it in a group.
Without even looking at the solution I can spot the implicit meaning of "oldest child". But just because he is the oldest does not mean the oldest 2 are not the same age. As an example, one can be 24 and have a sibling 24 as well.
Or older and younger twins. I know a number of twins and the oldest does get referred to as "oldest."
the work in class: 1+1
the homework: find x
the test:
I'm honestly shocked that when the question was asked I was like "Oh it has to be 3, 3, 8." not even having a reason why
Bad puzzle from the wording. As said many times two children can be born within a year, so the age would be the same regardless of one being 9-11 months older
As someone who lives with twins, there is an Oldest Twin and a Youngest Twin. I tend to forget who's who, but that's my problem. If you said "Oldest child" I would not at all assume that your children have any difference in age from that.
"..but commonly this doesn't happen." That is where your argument went out the window.
The ages also might be 2304;1/16 and 1/16 ???
That would mean his house number (street address) is 2304.125. I've seen house numbers with "1/2", but never "1/8".
The one jump in logic is the one he mentioned (about “oldest”). The second, even bigger leap in logic, is saying that the only reason census taker can’t figure it out because there are 2 possibilities as opposed to the census taker just not wanting to do math.
Or the census taker had better things to do than waste time on riddles when he just wants to fill in the form and move on to the next house...
Assumptions built into 'logic puzzles' is a bit of a cheat, as we can all make whatever 'reasonable' assumptions we want, and come up with other possible answers (or that there is no unique solution).
I think this is much easier to do in your head if you skip all that listing and go straight to the 2 + 6 + 6 = 14 because 36 is the highest square factor of 72. I'm far too lazy to find a pen and paper or to open notepad.
Then, you can just poke about and look for some other likely numbers that add up to 14. 24x3 is the obvious place to start because there's lots of ways to make 24, and it's the next biggest factor.
Actually the next highest square factor after 36 is 9 which is already far too small: 3*3*(
The thumbnail got me to click because I had to find out if the puzzle was trying to claim that calling one child the "oldest" means they couldn't be a twin. That's the sort of loophole that could actually be the solution to a different logic puzzle.
First i thought their ages are 3,4, and 6 when i'm solving before the answer was shown
Actually, the ages could be any combination (that makes sense, not the 1, 1, 72 or the like) because the census taker could not be bothered with the mathematician's bullshit and decided to move on
I just guessed 9, 4 and 2
James Dong i did the same, 2,4,9
tannacy jack me too
Me as well
3, 4, 6
@@tomekduresov706 my answer as well.
I'll still love chocolate chip cookies at 72
after looking at the puzzle i realised that the census taker is a bigger mathematician than the mathematician himself.
I actually got this one! I'm so proud of myself!
Before watching the video: The children are 2, 4 and 9 years old. 2 x 4 x 9 = 72 and the house number would therefore be 17.
If there's no hidden secret within "chocolate chip cookies" (like a meaning behind it being an alliteration or counting the letters etc.) than the oldest child being 9 makes sense and the highest number can't be used two times, but still has to be somewhere in the range of being a child and not a teen yet. ;)
I had the same thought. C is the 3rd letter in the alphabet and therefore "chocolate chip cookies" either equals -3 (substracting) 1 (dividing) 27 (multiplying) or 9 (addition). Since the first three are not possible to arrive at 72 within the given rules, you could conclude that the phrase "chocolate chip cookies" is a riddle within a riddle hinting to the number 9.
The problem is, that we never got the information that the census taker knows the house number. Even if he visits the house there is no way to know that he has the house number in the first place.
To argue that he has to know, because he needs to get to the house is not plausible for me. Because it is just an assumption. Just as we are assuming that the mathematician talkes about ages in years and not months (for example the children could be 2,2 and 18 months old) or that he rounds their ages to natural numbers and not in increments of half a year.
Since the riddle is never stated as a purely mathematical puzzle and lives off of baseless assumptions, there can never be a definitive answer.
Correct Answer: Write in "refused to answer" and move on to the next question.
But can be the oldest for only 10 months and have the same age of his brother
Got it! Even though I have no maths beyond arithmetic, thankfully 72 is a relatively easy number to break down by trial and error. The logic part, the relationship between the three clues, was fine for me.
Twins are guarenteed that one will be a couple minutes older
+Weeping Dalek Didn't think of siamese twins, did you?
heh
one still tends to come out earlier, even if it's a toe
Read from the old testament, lol
Unless someone has a really, really screwed up birth
And the census taker replies, "You're wasting tax payers' money as you're wasting my time!
You are fined to pay an amount equals to the sum of the ages of everyone in this country every year during a period of time equals the product of the ages of everyone in seconds."
^_^
Census workers are hourly, and work until work runs out. So if every house went really slowing, there'd be more work and more hours for the worker: more money! Where as the fine would NOT go to worker: so more riddles please!
@@CouchPotator I suppose you must be kidding (like I did), aren't you?
I don't know which country you're in, but there I am, census takers don't have hourly salary. But rather, they have to finish their work of the day even if they have to do over-time, but no extra pay.
@@Horinius yeah I wasn't being serious. Though I live in the US and that is how census jobs work here. If you're also US, maybe it depends on the state or temporary vs. permanent staff?
This incorrectly assumes you never met any twins. My father was a twin, and him and his brother constantly was making sure everyone knew who came minutes before the other ...and who was the OLDEST. :-)
Bad problem, beacuse:
1. Census could have been bad in math, and that's why he couldn't solve the problem.
2. He may refer to older twin as the oldest child.
I was only able to figure it out halfway...
"The product of their ages is 72" - Ok, that narrows it down to 12 possible combinations
"The sum of their ages is my house number" - I don't know the house number!
"The oldest loves chocolate chip cookies" - Ok, so the oldest is old enough to have teeth, which doesn't actually narrow it down since the oldest in all the possible combinations I have so far are all 6 or older, so this doesn't actually help at all!
I then proceeded to fume over how unfair it was that the census knew the house number and I didn't, since it seemed like I was supposed to figure it out using the same information that the census was given. But I was never actually given the house number, so the census had more to go on!
If I actually knew the house number, I could have at least narrowed it down to 2 possible combinations and then try to figure it out from there. (Then maybe the cookie clue would've been more obvious.)
This is the most amazing Riddle I have ever seen!!!
Awesome!!!
Brilliant!
Welp twins can be older than each other and assuming he wouldn’t say that is a dangerous assumption.
The father provides that bit of information after the censor gets stuck between two possible answers, and also he words it in such a manner that it's clearly meant to provide the final piece of the puzzle. If he had two eldest twins, that final piece would mean nothing or, worse yet, would be unfairly misguiding. Also, he's a mathematician. When he mentions "the eldest" in the context of an algebra problem involving the unknown ages of several individuals, he's definitely singling out the highest number in the ecuation, which means that there's just one of them.
Did he really spend that much time talking about how you can deduce two children dont have the same age? And then verbally say all the combinations of ages?
Sigh
Come to think of it, this problem has infinite right solutions.
Amazing riddle. If you want to make prople go really nuts when you describe the given, let the question be "what are the ages of the children and what is the number of the house".
It would be helpful if you clarify in the question that the census taker is a bright mathematician.
I got 2, 3, and 12.
same!! I just randomly thought of it
Wrong. In this case the census taker would have known the age already with the first clue.
B
Same
Me too
1:56
You know you can um
Re-record that
Scam School did this one too.
+Patrick Dukemajian Yep, +1 for that observation fellow scammer XD
I have ALWAYS been the middle child despite having a twin. My twin has ALWAYS been the youngest. Saying you have an oldest child is meaningless when that's how we refer to twins.
The census taker has the advantage of knowing the house number! 3, 4 and 6 works but few houses are numbered 13, typically 13 is skipped as the odd side is numbered 9, 11, 15, 17.
Mathematician: **tells him the riddle**
Census: “Actually, I don’t care. I just tried to be polite and communicative. And also you are weird”
as soon as he showed the sums, it was easy to figure out. you just gotta know where to start and getting to the end is smooth sailing.
It's a cute riddle, but it fails on at least three grounds. First, it's not certain that the census taker knows the house number. Public records of house numbers aren't always correct, especially when new houses are being built or one house is being converted into two or more. Many houses have names, not numbers. In the UK, a census taker wouldn't visit a house unless there was something unusual - censuses are usually done by post or online. So the fact that the census taker has a reason for visiting the house throws some doubt on this clue.
Secondly, when the census taker says he can't solve it, that doesn't mean that it can't be solved - ie that there isn't enough information. It could be that the census taker wasn't very good at maths.
Thirdly, the "oldest child" clue fails on multiple levels. An oldest child could be the oldest of twins, adopted or born 9-12 months after the second oldest. If the parents have remarried, they could each have a child from an earlier marriage with identical ages but one being clearly older than the other.
Am I nit-picking? Maybe. But when the solution relies on nit-picking, I think it's open season for nit-picking on the question.
What is house number?
Very clever. I missed the most important detail, that the census taker suddenly knew the answer at the end.
I thought the census taker was just a bit slow, and then finally came up with the (wrong) answer! ;) ps. There is also an assumption that the mathematician was telling the truth....
It's that second step that got me (finding the factors and looking at the possible house numbers). I've seen puzzles like this before and it's always a blind spot.
Why is it assumed that the census taker is willing to sit there and work this out? He's got a job to get done, and isn't likely to put up with this mathematician's BS.
0 children, next house.
you don't actually have to write down the whole table when you think through the situation in reverse order. The last hint the census taker needed is that there is an oldest son, which means before that there were 2 age distributions adding up to the same house number, and one of those is with the 2 oldest children having the same age (which is the one eliminated by the last clue).
Looking at the prime factors, the only possibility to get 2 equal ages without the third one being larger is 6,6,2, which adds up to 14. Now you only have to figure out another possibility to get to 14 (just with trial and error), which is 3,3,8
Mathematician: Solve this riddle to determine the ages of my children.
Jet Li: In Hong Kong, you'd be dead.
3, 3, and 8. First, write down all sets of three numbers that have a product of 72. Then, realize that the cookie hint implies that there IS an oldest child. Therefore, in order for that hint to help the census worker, the house number must be the sum of the set of three numbers that has a tie for largest: 2, 6, 6. Sum them to get 14. That is the house number. The answer is the other set of three that sums to 14. That is, 3, 3, and 8.
"Chocolate Chip Cookies" was used as a trigger, in the MKUltra trials, that switches the deactivated brain into conscious mode.
When the mathematician said the magic word, the census taker remembered he had a brain and that he knew the mathematician's address, so the calculation was simple. The Census taker quit and set up Amazon.
Okay, this problem requires a couple of assumptions which just aren't always true. First, that the parent would refer to a child as "oldest" _only_ if the child isn't a twin, and that the census taker is good enough at math to come up with valid values for the children's ages. When I was a kid, I had friends that were triplets, but they knew who was the oldest, and often referred to her as the oldest. As far as the valid values go... I know we can all think of someone with a learning disability. You can't just assume, by the wording of the riddle, that the census taker couldn't figure it out just because there were two possible values. He may have been confused by the riddle the mathematician gave him. Saying that he "understands" after being given the second "clue" may just mean he guessed an age for the oldest child.
Also the unwarranted assumption that the only way to have two kids in a calendar year is by having twins. It is possible for a woman to get pregnant even just a month or two after giving birth (not that many woman would want to, but it's physically possible), so a woman who gives birth on Jan 1 in a given year could give birth to another child in December of that same year. Thus two children in the same year who are not twins, making one of them indisputably older than the other. The answer given relies on an unwarranted assumption. But then all these "unsolvable" riddles ultimately rely on unwarranted or unjustifiable assumptions. It's pretty garbage. But hey, it makes for great youtube content - the amount of views and interactions these videos get is through the roof. I bet the channel owner makes tons of money off of this stuff. And at the end of the day, that's the only kind of math he really cares about!
I love how these people being given these questions in these scenarios are treating this like it's everyday stuff
It assumes the census taker knew the two possibilities. From the question, it does not imply so.
This is one of my favorites, but I learned it as a mathematician guessing the ages of another one’s children. I’ll always remember that it’s 3, 3, 8.