Can You Solve These "Ghostly" Riddles?
ฝัง
- เผยแพร่เมื่อ 15 มิ.ย. 2024
- This video includes 3 puzzles that ghosts are useful mathematically. Can you figure them out?
Puzzle 1: A father left 17 goats to his three sons. His will promised 1/2 of the goats to the oldest son, 1/3 to the middle son, and 1/9 to the youngest son. But the sons could not divide 17 evenly. How did they split up the goats?
Puzzle 2: You have several identical bricks and a ruler. You want to measure the diagonal of a single brick without using any formulas. How can you do it?
Puzzle 3: At 6 am a monk started climbing a mountain and reached the top at 8 pm, where he slept for the night. The next morning at 6 am he descended the mountain on the same path and reached the bottom at 8 pm. A mathematician made an interesting observation: by the facts, there must be some spot on the mountain that the monk occupied at exactly the same time of day for both trips. Why is this?
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I have 20 sweets and have to give half to a friend. How do I do this? Invent 20 ghost sweets, bringing the total number of sweets up to 40, then give my friend the 20 ghost sweets.
+Katzen4u 😂😂😂
+Katzen4u Lol
+Katzen4u i have 20 sweet. and i give half to my friend. how many sweets do i have left? 10? no 19.5 i just gave him half. not 10. these are mine sweets he should be happy i shared
😂😂lol
Lol
4:09 So the monk had the ghost goat the whole time.
No, the ghost monk had the ghost goat ;-)
+RedTailedDolphin and the ghost brick
+William Pereira Gomes no, the ghost monk was actually an undercover ghost goat
+William Pereira Gomes so many ghosts here I have to call ghostbusters
Dat Epic Fish Who do you call? GHOSTBUSTERS!
1) two of the sons "disappeared", leaving all of the goats to one son. He is haunted by the ghosts of his brothers to this day.
2) a stone carver cuts a brick diagonally. After the measurements, the brick feels phantom pains from it's missing half.
3) the monk slept in the same position for the same two days. He was late to his duties, "ghosting" several people.
The most accurate answers to each of the question.
Actual solution for number 1: Breed them.
LOL
What if they're all male goats? 😂
@@peacefulnuke7690 it's 2020, don't you know? Males can get pregnant, bigot
@@eomoran Lol
"Today on how it's made"
The people or the goats??
Since I don´t believe in ghosts, I place the 3 bricks in line, one after another, remove the middle one, and measure what I want...
+Paulo Bouhid Alternative answer
+Paulo Bouhid That was my solution.
Since I don't believe in ghosts, I draw a graph of time and distance to the top of the mountain for the first day and one for the second day. It becomes obvious that the two graphs have to cross somewhere.
I applies the same method..😀😀
U would have to cur ur ruler a little bit though on the edge of the rulers
I've heard the goat riddle before and never agreed with it. I never really liked it, because at the end of the day, each son got more goats than he deserved, leaving the dead father unsatisfied.
It's not about absolute number of goats, it's about the ratio
Middle kid got 3 times as many goats as youngest kid, and oldest kid got 50% more goats then middle kid
But that's not what the father intended, becaus 1/2+1/3+1/9 does not equal 1, meaning that the father didn't want to give all his goats to his 3 sons when he died.
That's like me saying that when l die, l want you to have 1/2 of all my money. You soon find out that l have 11 dollars. So you borrow 11 dollars from your friend, take half of it and return the 11 dollars. You took half of the 22 dollars, but you took 100% of the money, not half of it.
Well... 1/9 + 1/3 + 1/2 doesn't equal to 1
yeah, in fact, 1/9 +1/2+1/3 = 17/18 which is what the father need
If you get more than what you deserve, you better be happy!
My reason for every answer I get wrong in a math test from now on, is that there was a ghost goat there somewhere.
the Ghost Go...Ghost monk ... that made me Lol 😂👌
i don't have words to say
@@alimetlak Hey, that's pretty good
"So how would you divide 17 evenly according to these fractions?"
Me: Wouldn't that be funny if they just caught another goat?
"You just add a ghost goat....."
Me: O_O
My solution to the first one was:
Shred all the goats into meat and marrow
Weight the total of it
Give half to the oldest and 2/3 to the otherone and let the smallest have the bones
not so fancy but it does the trick
+Roque Moreno Well, the father didn't specify the general health condition of the goats.
+Roque Moreno me too
+Roque Moreno Then you throw the remaining 1/18 of goat flesh to the dogs?
+Roque Moreno what you are supposed to do is change the fractions so they are the same. 1/2 1/3 and 1/9 9/18 6/18 and 2/18there is an even fraction and 2 uneven fractions in there. so what you need to do is make it all even fractions. you can do that by doubling the fractoins. (even times uneven equals even, and even times even also equals even) so you get 2/4 2/6 and 2/18. yay all even. now we need to match the last numbers. start with the biggest. 2/18 ok 6 fits 3 times in 18. so 6/18 ok four fits 4.5 times in 18. aw crap. but wait. 1/2 fits 9 times in 18. ahh so we get. 9/18. yay it works. the "ghost sheep" is just a clever math trick. basicly a shortcut. that only works with these numbers. because change around the value's and suddenly you need more then 1 ghost sheep. and goodluck guessing the right amount. ofcourse i just straight up doubled 1/9th and then matched 1/3 to 18. and 1/2 to 18 because only stupid people double all at the same time. just double the biggest one, and then try to match up the others. untill it works.
Uh... you can’t.
Whats the square root of 2?
Add seven to the two to make the answer 3!
so what ur saying is square root 9 = 6
because 3!=3*2*1=6
No, he is saying the square root of 2 is 6.
Noah Linning oh that makes more sense
SpartanSpark No, he's saying that the square root of 2 is 3.
SpartanSpark
#sarcasm
4:13 "his ghost goat... his... the monk is coming down" 😂
I cant stop lol until my stomach hurts 🤣🤣🤣🤣🤣
3) Let f(t) denote the monk's position on the trail going up the mountain. Let g(t) denote the monk's position on the trail going down the mountain. Note that both g and f are continuous.
Define h(t)=g(t)-f(t).
h(6 AM) > 0
h(8 PM) < 0.
By the Intermediate Value Theorem, there must exist a c such that 6 AM < c < 8 PM and h(c)=g(c)-f(c)=0.
So at time c, g(c)=f(c).
yep, i also did think about this version of solution
Also the monk slept in the same spot at the same time at the top of the mountain and then woke up too. This means that the monk must be there at the same time.
If you remove the gost goath then 9 goats is not 1/2 anymore
For one, recognize that each of them got more than his fair share. 9>8.5, 6>5.67, 2>1.89 .
Reason being that 1/18th of the inheritance (17/18th of a goat) is undivided (9/18+6/18+2/18=17/18). Let's say the sons are really autistic and want it exactly right, and thus have taken their deserved goats, and used magic markers to draw up their portions of the remaining 3 goats.
Son A has taken 8 goats, and marked 1/2 of the 15th goat.
Son B has taken 5 goats, and marked 2/3rd of the 16th goat.
Son C has taken 1 goat, and marked 8/9th of the 17th goat.
Thus they notice there's a portion still undivided, and they take their markers again. After some heavy calculations, son A marks half of 17/18th of a goat (8.5/18th) on goat 15; son B marks a third of 17/18th (5.67/18th) on goat 16, and son C marks a ninth of 17/18th (1.89/18th) on goat 17.
Son A now has 8 goats, plus 35/36th of goat 15
Son B has 5 goats, plus 53/54th of goat 16
Son C has 1 goat, plus 161/162nd of goat 17
They're again left with a piece, namely, 9/324 plus 6/324 + 2/324 = 17/324th of a goat (that is, 17/18/18).
As you'll notice, with every repetition they are left with that 1/18th piece of what they had left, to repeat ad infinitum. So you might write Son A's inheritance as Sum(n=0-infinity) of( 8.5/18^n), which equals to 9. That is, as the sons keep adding their share of the remainder, each step they'll get closer to the 9/6/2 split.
I'm a bit late on this.. but...
Son A:
17 = 100% 17/2 = (100/2)% 8.5 = 50%
Son B:
17 = 100% 17/3 = (100/3)% 5.6(recurring) = 33.3(recurring)%
Son C:
17 = 100% 17/9 = (100/9)% 1.8(recurring) = 11.1(recurring)%
And obviously, you're not gonna get a fraction of a goat, unless it's to eat, so:
Son A wold get 8 goats, and half of one to eat, or either 8 or 9 goats, depending on how they decide it should be rounded.
Son B would get either 5 or 6 goats, and if he got 5, he could be given about one third of a goat to eat.
Son C would get either 1 or 2 goats, and if he got 1, he'd be given a large majority of a goat to eat (approximately 8/9).
Then the rest of the goats could be sold, and the money equally split between them, or something else, like the goats just being given away.
Also, after doing this I kinda forgot why the person i was responding to did the maths they did... because of the original comment, and to that I say, no, it's not 1/2 anymore, it's 17/9
jimmy rietveldt It's a real story. Or at least a legend.
actually the father's wished a wrong share as the total of all parts is not being equal to 1
1/2+1/3+1/9
=9/18+6/18+2/18
=17/18
This shit doesn't even add up.
+Cheers! 진아 이야.♥ That's the point, this is pretty much bullshit :/
+Cheers! 진아 이야.♥ It doesn't add up. The father is either dumb or wants his sons to fight to leave this will. But in your working you proved why giving them 9, 6, and 2 is fair. So I don't see the problem with their solution.
+Cheers! 진아 이야.♥ The answer is that a dude comes along with a goat, adds his goat to the herd, gives one of them 9, one of them 6 and the last one 2, then he takes his goat and leaves. That way the proportions still add up, and they get the right amount of goats
+Cheers! 진아 이야.♥ Right, didn't watch the rest of the video, I just realized he had a solution....
+Melvin No then what if the numbers were diffrent? then 1 ghost goat would not cut it. because the vallue's are diffrent
I was wondering if you'd ever come across the goat riddle. I'd heard it as camels, and that the sons went a friend of the father for advice. He "loaned" them a camel, which then made the riddle closer to the "Missing Dollar at the Hotel" riddle. But in the end the same trick. Cool
The ghost goat is a lie.
The division for the three sons is incorrect.
one half and one third and on sixth makes one not one ninth.
Peter Scheen what are you talking about? Maybe rewatch the video
the goat division suggest that the the total of the goats is o be divided by the three sons. Well it is not. So that is why when it where 18 goats the first son would get half that is 9 goats, the second son a third, that is 6 and the third a ninth, that is two. That would make 17 not 18 in total so who would get the 18th goat? You see, one 18th of the inheritance is not accounted for.
The "ghost goat" does not solve the problem. By definition, an estate has a residual beneficiary. In this problem, the residual beneficiary is being cheated out of 1/18 of the estate
Peter Scheen To me, the goat division suggests the total number of goats is not 17. That is because if you sum up 1/2 + 1/3 + 1/9, you don't get a full unit. You get something like 17/18. This is why you could use a "ghost" goat to make calculations simpler.
Puzzle 1:
(a) The sons formed a limited company and benefited from the meat, milk, hides and kids in the specified ratios.
(b) They waited until a kid was born and took 9, 6 and 2 goats respectively.
(c) They weighed the goats and made three groups: one group half the total weight, one a third and one a ninth.
(d) The eldest son said, "This would be so much easier if there were 18 goats, which is the lowest common denominator of the fractions."
"Yes", said middle son, "then we could take 9, 6 and 2."
The youngest son counted on his fingers and toes and said, "Well why don't we just do that anyway?"
And so they did, resulting in years of expensive legal battles with their mother who claimed ownership of one-eighteenth of the herd. The four died estranged and penniless.
Puzzle 2:
Put three bricks end-to-end. Remove the middle one. Measure the gap from bottom left of Brick 1 to top right of Brick 3.
Puzzle 3:
Imagine that on the second day another monk copies the first monk's journey up the mountain. Buddha performs a miracle whereby the second monk's path and pace are step-by-step identical to the first monk's journey of the day before. The monks will meet somewhere. By definition, they meet at the same place and at the same time.
the first one blew my mind. however if you add up the number you see that
17/2 = 8.5,
17/3 = 5.66,
17/9 = 1.88
the combined number of goats is 16.04... the problem was that you couldn't distribute all goats if you hade't invented a 18th goat.
this means the father was stupid xD
1/2 + 1/3 + 1/9 is not equal to 1 thats what we had to observe basically.
just round all numbers up to the closest total. No ghost needed.
What do you expect from a father who treats his sons unfairly.
+Astfresser yeah, 1/2 + 1/3 + 1/9 = 17/18, a bit less than 1.
And 17/18 explains perfectly where that ghost goat comes from
+GaradurLP
One More thing that I noticed:
First son gets 9 (1/2 more than 8.5)
Second son gets 6 (1/3 more than 5.666...)
Third son gets 2 (1/9 more than 1.888...)
So of the remaining fraction of goats (0.96), the 1st still gets a half, 2nd gets a third, and third gets a ninth. Again you'll be left with another fraction (0.53). This process goes on indefinitely
Question 1. This trick question is commonly 'answered' by having an eighteenth goat temporarily borrowed from somewhere. No ghost is required.
Question 2. This merely makes use of the side-angle-side rule for triangular congruence. No ghost is required.
Question 3. I have seen this answered by invoking the scenario of having the ascent phase captured from afar using a movie camera, then having the footage projected onto the mountain throughout the descent phase. The image of the ascending monk must coincide with the descending monk at some point. No ghost is required.
Rabbid Sloth
Emphatically, I do not! The concept invokes no fear whatsoever in me.
Cheers ;)
+Jack Sainthill
Why would ghosts = fear?
+Jack Sainthill Nice try, but:
Q2: "side-angle-side rule for triangular congruence" - which requires calculation, thus rendering your solution invalid.
Q3: "having the footage projected onto the mountain throughout the descent phase." For all intents and purposes, that *IS* equivalent to a ghost in the context of this video. The "ascending monk" is an imaginary thing that isn't actually there.
LucisFerre1
Obviously I'm not the person to ask, am I.
LKC9215
1. No, I can visualise it without calculating anything. I dare say most of us can - but I'm sorry to hear about you, though..
2. A projected image is a measurable physical phenomenon, not an imaginary thing.
Like many trick questions, the first puzzle is sensitive to phrasing - the puzzle works when phrased as requiring the estate to be divided between the sons in that fashion, or as requiring the sons to inherit in that ratio, but not when it requires those exact fractions of specifically 17 goats (or camels, which seems to be the most popular version).
There's a version out there where the initial herd is 35 camels, allowing the person who solves the problem to take a camel as his fee for his assistance (or the person lending a camel to claim 100% interest on the loan)
Also "an old wise man" who adds his own old and sick camel only to take it back later
*Annabelle wants to know your location*
The first one is utter nonsense. Please tell me that was a joke. You can't find fractions of 18 and then claim the values represent the same fractions of 17. It's like me saying, "Half of 4 is 2, so half of 3 is also 2".
the 1/9 might have something to do with it. 0.1 recurring is a weird one since 0.1 recurring times 9 is 1
The introduction of the ghost goat just stops you from needing to round that's all.
E.g the third son gets 1.88 of a goat, round up and he gets 2.
Or he gets 1.88 of a goat plus (1/9*1).
+iSquared If you read the book "the man who counted" made by Julio Cesar de Mello e Souza (Brazilian Writer), you can see a similar puzzle with a explanation.
+iSquared
If you consider that the father gave the sons the ratio of how the goats should be distributed (1/2 : 1/3 : 1/9), then adding the ghost goat and seeing that it divides perfectly is a pretty eloquent way of finding the solution. I would do it this way: 1/2 : 1/3 : 1/9 = 9 : 6 : 2 which adds up to 17 when multiplying the ratio by least common multiple.
+orochimarujes My point is, regardless of the mathematics, which I do appreciate as a mathematician, 9 isn't half of 17, 6 isn't 1/3 of 17 and 2 isn't 1/9 of 17. So the problem has not been solved. The answer you have given is NOT a solution to the problem. Do as much maths as you like. The facts I've stated will remain unchanged.
1. - Get a sword
2. - Use a brick to smash part of it.
3. - They are the same path so...
Mr. Talwalkar, I love your videos. Here's what I did to solve Puzzle 1:
1/2 x 1/3 x 1/9 = 1/54.
Lowest common multiple of 17 and 54 is 17 x 54 = 918.
918 divided by 2, 3 and 9 gives 459, 306 and 102.
I divide these three numbers by their highest common multiple which is 51, and get 9, 6 and 2.
9 + 6 + 2 = 17.
I don't understand why that works though, since, indeed, 9 is not a half, 6 not a third, and 2 not a ninth, of 17. Can you please explain?
+crudehawk The puzzle was designed so that although they don't get 1/2, 1/3 and 1/9, they get the share in the ratio 1/2 : 1/3 : 1/9. What you did is you picked 3 numbers in that ratio (459, 306, 102) because you multiplied the same number (918) by 1/2, 1/3 and 1/9 (which is the same as dividing by 2, 3 and 9). When you divided them by 51, you preserved the ratio, so you ended up with the smallest triplet in that ratio. Of course, the puzzle may not use the smallest numbers, so you might have to multiply each of them, which is not the case here, but is in the following one.
Try this variation: 20 goats, 2 sons, shares 2/3, 2/7. Again, you can invent the 21st ghost goat, one gets 14, the other gets 6, then the ghost can disappear. How about your method?
it's easy when you add 1/2+ 1/3 + 1/9 =9/18+ 6/18 + 2/18 =17/18 in LCM ..that's y the ghost goat appears ......
This looks like that common core math lol.
The second one. What stops you from measuring the brick itself. You only need 1 brick, not 3. It's not that difficult to align the corners
We're trying to measure from the top left back corner, to the bottom front right corner, which would require you to line up through the brick, hence why we're measuring through a ghost brick.
Though this was not at all clear from the description in the video.
What else is opposite corners supposed to mean? Get your mind out of 2D mode lol
I have an alternative solution for the second puzzle: You put three bricks next to each other, then you remove the brick in the middle and then you can measure the distance between two opposing corners.
4:13 it was the ghost goat all along
(add an awesome detective music here)
the last one is the sandwich theorem in calculus basically
The solution I came up with for 1 makes a lot more sense imo: there were 18 goats to begin with, the father only left 17 to his sons, and the “1/2”, “1/3” and “1/9” refer to the total number, not just the ones going to the sons
It's also more confusing. Btw the fractions refer to sons not total.
1/2:1/3:1/9 is the ratio we want. Change them into whole number .
9:6:2 is the ratio of splitting between the sons. Here you go 17 goats. It's that obvious.
Like you say there always have been 18 goats because 1/9+1/3+1/2 adds up to 17/18 . They trick us with words.
It's true. Based on the fathers words, only 17/18 of the goats are left to the sons,
No ... The brilliance of the first puzzle is there is no way to split up 17 goats. So add in a "no goat" and they then split 17 goats + imaginary goat that's not there. That division of 1/9, 1/3 and 1/2 seems fair to get 9, 6 and 2 goats that includes the added imaginary goat fairly. 😂🤣 The three bricks problem makes little sense if the ruler is held in place on the side of only brick which is what you'd have to do with only one brick. With three bricks held along the ghost brick diagonal does the same thing as laying the ruler epsilon in on lower brick to not create significant error and friction may not hold ruler in place. Holding in place on the side of one brick is more accurate. The monk one is arbitrary and makes no sense unless the monk has to ascend at a constant rate and descend at a faster different constant rate not specified but in general
What if the 18th goat was the father who is now gone.
I hope this video was a joke...
4:10
so the father just borrowed the monk ghost goat
His ghost goat...
Presh : " Add a ghost goat and divide..
Me: " divide 5 by 3....
Add ghost 1 to 5 and divide by 3 we get 2 and then subtract the ghost 1 thus 5/3 is 1"
It's time for ghost review 👻👻😱😱
The total of divided goats get into 17 , how could it be ?? When we took 18 goats ,??
4:12 his ghost goat, eeehhhh, ghost monk
1. You cut some of the goats in half. wait... 1/2 + 1/3 + 1/9 = 9/18 + 6/18 + 2/18 = 17/18
So the oldest child gets 9, the middle child gets 6, and the youngest child gets 2.
2. You use the ruler.
3. Because he took the same amount of time each day.
3. The ghost goat.
The middle one stumped me. My ghost-less solution was to balance the corner of one brick on top of another brick lying flat, and then balance the 3rd brick lying flat on the opposite corner of the upright brick - then measure the distance between the top and bottom bricks. While difficult in practice, this would work in principle because (a) a line connecting the middle brick's opposite corners will pass through its center of mass so it should balance, and (b) the top brick will be exactly level.
1st one is total b****hit, the oldest some should have gotten 17/2(8.5) goats, but he've gotten a half a goat more, then his father desired
+FreakingDuck straw man argument. Idiot.
+ZzzesChannel Except we have to consider entire goats, therefore there is no perfect solution. The closest approximation was what was explained in the video.
+FreakingDuck Has this channel been passed around 4chan or 8chan?
*****
There's usually only a few comments, yet there's a sudden surge of comments, and "muh [something]" is usually said on chan sites.
The only video where Presh says 'Pythagorean Theorem'....well everyone knows what he says in his other videos....no need to say😂😂
In this video, he said Pythagorean theorem because he didn't use it... if he had said the other name, some of the viewers will be kept wondering what that means... :)
I got the first and third one right (yey for me, I guess) but didn't really understood what was wanted in the second puzzle till watching the answers. Maybe it was just me, but if you said "measuring an internal diagonal" I believe would have been really clearer.
Haha!! I had no idea what the question with the bricks was asking either. I was like, "uh...don't you just measure from one corner to the next? You don't even need the other two bricks."
i thought the same lol
+magnum567134 Well, it's hard to measure through a brick. Because you're measuring the complete opposite corner.
for the second question, no 'ghost' is necessarily required. The way I did it was put all 3 bricks side by side so the longest sides are touching. Take out the middle brick and then measure it like that.
yeah, the fisrt riddle is kinda stupid, even if 1/2+1/3+1/9 was equal to 1, you still cant just decide you add a ghost goat that doesnt exist and give evrey son more goats than he should have gotten. the riddle only "works" cause the fractions dont add up to 1 (take the word "works" with a grain of salt because the sons actully get more then they deserve according to the fathers will)
Their mum doesn't get any
+WTF Google+ do you think this is a normal usermame? whats wrong with you?!
1/18th of the herd is not accounted for in the will. Since the father did not specify who gets that share, the next of kin have the right to settle it amongst themselves if they can come to an agreement. Assuming the father wrote his will ahead of time, he did not know exactly how many goats he would own at the time of his death. So he was actually smart to leave some wiggle room.
For question 1, you grab a knife and split a goat into smaller pieces. The ghost in that question is actually the ghost of the dead goat.
That was my thought process on that question as well.
Goats -- just round. No ghosts required.
1/2 X 17 = 8 1/2 rounds to 9.
1/3 X 17 = 5 2/3 rounds to 6.
1/9 X 17 = 1 8/9 rounds to 2.
Or ignore remainder.
1/2 x 17 = 8
1/3 x 17 = 5
1/9 x 17 = 1
The three remaining get divided equally, not quite following the will.
....
9/18 + 6/18 + 2/18 = 17/18. Does 1/18 go to the daughter?
no, eight inches goes into the daughtet
p.s. goats are more valuable than daughters anyway
The first puzzle I solved easily. The second one was an interesting solution. The third... I admit I didn't manage to come up with a solution.
I’ve once heard of the “potato crisp theorem” which says that it is always possible to cut out two identical chips from different shaped potatoes, and there are an infinite number of ways to do so. Use ghost potatoes and phase them through each other, cut along where their skins meet and that’s the shape of the chips from both potatoes.
That ghost goat will haunt me in my dreams. Glad he didn't add a zombie goat. That would have been terrifying.
The puzzle still doesn't make much sense though. Either the father implicitly meant "_at least_ a half, a third etc." in which case you could just calculate the fractions and round up or he meant "exactly" in which case no, you can't make the ghost goat disappear. The father was also mathematically challenged and a huge dick to his youngest son.
Actually the youngest receiving 1/9 would have been on par with ancient inheritance rules. The oldest is actually getting less than he normally would. Usually the oldest gets 2/3. The middle would get 2/3 of the remaining 1/3 or 2/9. The youngest gets 1/3. If there are more male children then you keep dividing the remaining 1/3 the same way.
His ghost goat. His g... The ghost monk. XD
Awesome video, didn't get the first,
Though plot two curves on a position time plane and if they start and end at the same place they must intercept at some point. But now thinking about it that's not true. Fail.
*for the third, not the first.
+Dean Cook So in the first problem, if you add the ratios you get 17/18. Using this denominator you can divide the goats. Hope I could help!
+Dean Cook Actually you're kind of right. if you plot two continuous curves that start and end at *opposite positions* (which is what the question asks), the curves have to have an intercept.
1 and 3 are easy, but I was stumped by 2. Nice solution.
bro..... only the two of us think that... everyone else found 1 more difficult, at least that what I see in the comments
+Keshav Kasat I only had trouble with 3. Took me way longer to figure it out than it should've. The other two were easy for me, though number 1 is a bit bullshitty.
Puzzle 3 is simply ROLLES THEORM
04:13 GHOST GOAT
Puzzle 2 - Why do even I need the other 2 bricks when I've got the 1 brick that I want to measure & I've got a ruler? Anybody? No? Just me?
Because you're trying to measure opposite corners, ie the corners that you would have to travel through the center of the brick to measure. If the bricks were rectangles (2D) instead of rectangular solids (3D), then you could measure opposite corners with just one brick.
Teabag, which face of the brick do you propose you would measure to answer the riddle? There are three possible answers that way. If you go with 3D the question is not ambiguous.
Well, you can't do it with one brick, but you could do it with two, if you just removed the second brick after you marked the position of the bottom corner. You *could* theoretically do it with 1 if you could mark both points, but then you'd need something other than the ruler to mark a floating spot in the air.
"You cant devide 17 goats equally in half"
"Who said I couldn't?"
**brings out a knife**
3:18 why do you need a ghost brick? just place the ruler across the bricks, its easy
Only losers use ghost bricks. Arrange the 3 bricks in a row, and remove the middle brick.
The arrangement should be:
B_B
where a B is a brick.
Then measure the bottom left corner of the left brick to the top right corner of the right brick. No ghost brick needed ;)
+Flaming Obsidian You are still using a ghost brick, the only thing you did was change its location.
Try the ghost goat instead
Only losers use 3 bricks, I use only one :D .. Press the brick on the ground so you see its shape drawn, then put it next to it, now all you need is to measure from the bottom left corner of the rectangle on the ground to the top left corner of the brick.
The thing is, for the goat one, what happened if he wished for 1/18 of his goats to go to another recipient? You can't assume that he meant for all his goats to go to his sons, and you can deduct that if the fractions didn't add up to one, there was probably another inheritor!
4:13 "his goast ghot is.. the goast monk" lol 🤣
I am fascinated by your videos!
All of these riddles are stupid.
1. 1/2 of 17 isn't 9, 1/3 of 17 isn't 6, and 1/9 of 17 isn't 2.
2. You need to word this better as I thought you were talking about from corner on one side of the brick, so the riddle didn't make any sense.
3. The way you worded it is misleading as it makes it sound like you have to figure out why he was at that spot.
+Henry Rosenberg
Too bad for you.
Anston [Music] What?
+Henry Rosenberg First one was stupid I agree, most importantly because 1/2 + 1/3 + 1/9 don't even add up to 1. They should've just bought an 18th goat, split the difference evenly and then split the goats as per the fathers wishes. It's goat curry for dinner either ways.
The second was good. It was clever. The third was too easy. But whatever...
+xXxBladeStormxXx how was the second one good? WHy couldnt you just mesure one of the bricks instead of creating a ghost?
+Cloud Dino you weren't supposed to measure a 'side' diagonal of a brick in the second one, what you really had to do was find the actual diagonal of the cuboid. I know you're probably thinking that we had to measure the diagonal on ONE side of the cuboid, but that's not the case.
Just to make this more visually simple, think of a cuboid. It's 3-dimensional, so it has 8 corners: a top-right-back corner, a top-right-front corner, a top-left-back corner, a top-left-front corner, a bottom-right-back corner, a bottom-right-front corner, a bottom-left-back corner and a bottom-left-front corner.
Take your time to visualise all that. Once you've got it, draw a line connecting the top-right-back corner to the bottom-left-front corner. THAT'S really what the question asks you to find. The reason you couldn't do this with a real brick is because you'd have to put your scale THROUGH the brick.
I hope you get what I mean. Read the comment over again if it's not clear.
The first puzzle blew my mind!
Puzzle 1:Common Denominators
1/2, 1/3, 1/9
9/18, 6/18, 2/18
9+2+6=17 thus no ghost required
Puzzle 2:
Put one brick aligned with [a] brick's corner and edge, and the other brick aligned forming a cross(or twisted square; hourglass) with [a] brick's corner with only the corner touching, both bricks perpendicular to [a] brick. The distance between the closest lower corner and upper corner between the other bricks will be equivalent to the distance between [a] brick's opposite corners.
thus no ghost required
Puzzle 3:
50% or half way up would be half of 6am-8pm=1pm; 50% or half way down would be half of 6am-8pm=1pm,
thus no ghost required
I don't know about the first 2, but puzzle 3 is solved using the same logic that proves that there are always at least two antipodal points on the earth with the exact same temperature and pressure. If you denote the distance from the bottom as x, you can subtract the position of the monk at any given time on day 1 from the same time on day 2. The function will increase continuously (although not necessarily at the same rate) from -x at 6am to x at 8pm, so at some point in time it must hit 0.
The solution to the first puzzle is not correct as 9 goats is not half of 17, as the will specified. The puzzle should ask how they are split into an equivalent *ratio* to the will, not exactly according to the will.
I had a different solution to the second puzzle. Put the three bricks side by side. Take the middle brick away, and put the ruler in the gap.
The distance between the opposite corners can be measured just using 1
For the 1st problem how do you decide who gets to keep the ghost goat?
On the second one why not just measure corner to corner on one brick?
Second one can be done with 2 bricks as well, putting the second brick next to the first one and then moving it down until only the corners of the two bricks touch
That goat one. Wtf. You can't just magically make another goat appear.
Imaginary goat. Just like imaginary numbers. It's okay, as long as you make them eventually disappear again. :-)
Loved them! (Although I couldn't find the riddle in the second one until I saw the answer)
These are nice examples how to use math in a creative way! :)
First puzzle is mind blowing, incredible
I'm calling shenanigans...
Puzzle 1: 1/2 + 1/3 + 1/9 does not add up to 1 (1/2 + 1/3 + 1/6 does). Using the father's will, the eldest son would get 8.5 goats, the middle would get 5 and 2/3rds, the youngest would get 1 and 8/9ths of a goat... and the inheritor of the remaining 17/18ths of a goat is not specified by the will and will (depending on when this occurred) revert to the eldest son in accordance with primogeniture OR be tied up in probate court until the goat has already died.
Puzzle 2: If you have something capable of measuring the space between two bricks, couldn't you just... measure one brick?
Plot twist: the father also specified to give rest of the goat, that is 1/18 of the goat to his only daughter
The first two puzzles do make sense. I think the third one perhaps doesn't.
I solved first one, was almost sure that bricks must be placed one above the other, but couldn't solve second and third puzzle.
Borrow a goat, now you have 18. Give 9 to oldest son, 6 to middle son and 2 to the youngest one. Now you can return the extra goat and everyone is happy.
What about the person who was supposed to get the last 1/18th of the herd?
Nukestarmaster, there is no such person.
The goat riddle is old and famous but it doesn't actually divide 17 accordingly.
I would just measure one brick from the side.
The picture of that mountain implies that there might be more than one route that have the same length.
just a clever thinking help method.
2:03
MYD: A ghost goat
Me: cut one goat into parts so it fits the specifications
For the brick riddle.earlier u said no formula can be used but u used pythagora s theorem.
Secondly if you could measure the distance between two bricks.u could also measure the length of the brick directly.
It's all fine and dandy until their mum realises that she was owed 1/18 of the goats.
+Dan Dart Ya mean 3/18ths of 17 goats?
For puzzle 2 you can do it with 2 brick if you set the bricks on top of each other then rotate both to the long thin side and rotate one of them back flat. Go from the bottom of the upright one to the top of the flat one.
I solved the second puzzle in a slightly different manner. What I did was that I kept the 3 bricks adjacent to each other in a row, and then I removed the middle brick. This will create an empty space between the 2 bricks on the either ends, and since the bricks are identical, I could measure the distance between the 2 vertices.
2) Put the bricks corner to corner to corner, so they are arranged diagonally, take out the middle one, and measure it.
3)6am-8pm doesn't mean during the same day, could've taken 1 and a half days(aprox.) up and down.
Taking common ratio, of 9:6:2. We can devide the goats
The monk puzzle is also solved by drawing a height vs time graph and plotting the curves on the same axes. However you draw the graphs they must cross somewhere. At that point the time and height are the same.
I thought a good solution to the third problem is if the monk went way faster down the mountain than on the way up. That way, he would be able to reach a point near the bottom at the same time of day. The monk is tired so he decides to take a break or just walk very slowly so that he reaches both ends at 8pm
For the brick one, I was thinking of put all 3 of them side by side and remove the middle one.
Would the brick one also be solvable by putting all three bricks in a line, end to end, and then taking the middle brick out?
Oldest gets 9, second gets 6, youngest gets 2 and the threat of getting beat up if he complains.
On the brick one my solution was to lay them together horizontally and then remove the middle brick measuring from where the two edges of that brick would be
The Ghost Goat is after The Ghost Monk for laying a Ghost Brick. (in reference to the word slip on the last example.
I can't stop my self commenting ''THIS IS AMAZING''
Remember, naughty children get a visit by the ghost monk and his pet ghost goat who will throw ghost bricks at you when you are sleeping
2nd One instead of doing all that, you could just place the ruler against any brick and measure it
1) Use 18, the ratios don't add up to 1, so 1/9 of 18 is 2, 1/3 is 6, 1/2 is 9, 2+6+9=17
2) Lay two bricks flat end-to end, and put the third brick on top of one. Measure from the corner of the single brick to the opposite top corner of the brick laying on top of the other one
3) Imagine a second monk making the same ascent on the second day, they have to cross at some time. You could also graph distance on the path from the bottom vs. time and those lines have to cross.
Can Q3 be considered a variation of the Borsuk-Ulam theorem?
the problem with the first puzzle:
1/9 + 1/2 + 1/3 =
1/9 + 4.5/9 + 3/9 = 8.5/9
the father didn't divide the goats correctly, they're left with a 0.5/9 goat that goes to no one. that's why they all ended up with more than their share, not because ghosts, but because there was actually extra portions of goats
The first puzzle might make sense if one of the goats was pregnant and gave birth by the time it came to divide up the goats. 18 goats. First son gets 6, second son gets 6, and third son gets 2. And one goat doesn’t go to any of the sons, since the father only wanted to leave 17 goats to his sons.
So how many goats would 2 sons get if the father would wanted to divide them exactly by 2?
Yay, I got them all! But can someone explain the reason behind the counterintuitive division in problem one?
The fractions don't add to 1, so the problem doesn't lend itself to a proper solution.
I can mesure the corner to corner distance of only one brick. Measure its shadow. sun rays can be considered parallel in this case.
Honestly,my answer on puzzle number 3 it is because it is a isosceles Triangle..if the monk speed going up and down is constant...LOL