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blind person: *exists* the nine other prisoners: yeah we're screwed

only one serious problem of this riddle : everyone must understand your plan

Even if one person in the group could figure this out, imagine trying to explain this strategy to 9 other average humans in 5 minutes.

Realistically, the aliens would've also said that they aren't allowed to touch their hats, or otherwise remove them from theirs or each others' heads, to prevent them from just looking at their hats or switching them around.

Me an intellectual: *takes off my hat and looks because it’s not against the rules*

"Now it all comes down to you, in the front of the line." *Curses genetics for making him short*

3:25 Was this whole thing just a setup to call me short? Because you're absolutely correct, and I applaud you for calling me out in such a subtle, yet clever fashion!

We did this in special ed class a while ago, and it was quite a traumatizing experience, as my classmates didnt explain it to me and I kept failing everytime, so I went crying in the corner

Imagine everything is going as planned and the last person calculates his colour wrong and everyone dies

Unfortunately when you pick 10 humans at random there's gonna be a lot of idiots

This can be extended to any amount of colors. Let's say we have three colors red, green and blue. First we assign a value to each red=0, green=1, blue=2. The person starting to guess a color adds up the color values of each hat he sees and takes it modulo 3. For example for a lineup of (r,g,g,r,b,g) the sum would be 1+1+0+2+1=5%3=2, so he says blue. The next one does a similar calculation 1+0+2+1=4%3=1 and subtracts this from what the last person has said, leading to 2-1=1=green and so on. Interestingly, the riddle gets simpler if you use an infinite amount of colors. Again assigning values to them, and for simplicity just consider the values instead of colors. The person starting simply adds up all the values and says the corresponding color. Now the next person does the same and subtracts the result from what the last person said. So for a lineup of (12,2,43,29,1), the first one says 2+43+29+1=75, the second 75-(43+29+1)=2 and so on.

Wish me luck fellas, I'm going to binge-watch this entire series. Every single riddle. I'll update you all every riddle on how my progress is going. See you on the flipside!

Imagine actually coming up with this genius plan and spending the next 5 minutes carefully explaining it to everyone, just for the last person to screw up and cost everyone their lives.

"It all comes down to you" Me: wHiTe

One of the best riddles I have ever seen, Thank you Ted-Ed. Please bring some more videos.

“But their civilisation forbids eating highly logical and cooperative beings” That does not describe humanity at all 💀

"You have 5 minutes to discuss" Me: pull a out phone, shows video

Alternate strategy: Take off your hat and look. It's still allowed via the rules given

This is probably one of my all time favorite Ted Ed riddles!

my comp-sci teacher used to give us this problem when we started the logic module. it takes surprisingly long for a group of 12 year olds to figure out a solution for this.

Teachers would win cause they have eyes in the back of their head

honestly, if this plan was explained to me without any visuals within 5 minutes, i wouldn't even understand it 💀

이런 수수께끼들은 항상 다양한 관점에서 생각해 보아야 풀리는 것 같습니다. 정말 생각지도 못한 해답이었네요. 가끔씩 이런 문제들을 풀면 지루한 일상에서 벗어나는 기분이 듭니다. 앞으로도 이런 영상 많이 기대하겠습니다!

Adisson Anderson is legitimately one of my favorite people on earth. His voice is the one all of my positive thoughts are set in.

The aliens never said I couldn't take my hat off and look at it. Seems FAR easier than the explanation given in the video ;)

I don’t think anyone noticed but Ted thinks we are short.

this is actually nostalgia for me, used to watch this all the time with my older sister and i always remember asking "can we watch the colour riddle again"? (colour riddle as in this riddle). i miss those days damn

I understood it after watching it twice. It was very refreshing when I understood it.

Everyone: **uses the logic and remembers and gets their color right* that one person: purple, haha get it **everyone gets eaten**

That's really clever. Too bad you'd never be able to get 9 average humans to understand the strategy in under 5 minutes.

There are for sure several ways to get this correct

“Quick, What do we do?!” “No idea…”

"Can you think of a strategy guaranteed to save everyone?" "No, no, I can't."

"They're not sure if you qualify." O u c h -

People would die no matter what because there's always someone who just doesn't get it. Anyone who's ever tried to explain simple directions to more than a few people understands the frustration. 😂 I would try to reason with the Aliens first and say, "Look I have this awesome idea....but can I have a couple of practice rounds first so that I can thoroughly explain this and make sure everyone gets it? Or you can just eat me to put me out of my misery and just let everyone else go." 🤷🏽‍♀️😂

I don't think I could get my dumbass friends to do this correctly lmao.

I just love how Ted creates a backstory and then goes into detail to make it as logical as possible. E.g the universal translator app

I saw the solution immediately because I am aware of what computer scientists called a parity bit. It was a way of reducing errors caused by computer hardware. Say you have 8 bits (1s or 0s) to read. The hardware (such as a tape machine) would read the bits and then software would see if the total was even or odd. It would then compare that to a parity bit which had been set based on the correct answer. If the parity bit and the software calculated odd or even were not the same, then it would know there was a reading error.

You have to love Ted-Ed's riddles.

3:08 she looked behind her, EAT HER!!!

"...Unfortunately, they're not sure you qualify." *ROASTED*

It took me years of rewatching the video to understand why this worked

i don’t know why but when I watched this video as a kid it made me have trouble sleeping

This is the most ingenious riddle I have ever come across. It makes perfect sense, it's not confusing and the solution would clearly work, but I would never have figured it out, no matter how much I thought about it.

Then someone is sick and coughs and the aliens assume it's signaling and everyone dies. Edit: I've gotten 15 replies about Corona already, y'all ain't original.

this is the only one of these riddles that i’ve ever solved

Plot twist: Everyone is from a different part of the world and doesent speak the same language and we die since we cant understand each other

I get the riddle. It's smart. But can't help but not trust it since the odds of those 9 other people with me being morons are much higher.

Upload more riddles please

This is still the only Ted-Ed riddle I completely understand

Thanks TED-Ed, I now know what to do when I have to prove my logic to human-eating aliens! :D

0:48 Silly aliens, why would they turn the humans to ash if they misbehave, it means no more lunch. Who’s highly logical now?

Actually this is the only strategy that works to solve this problem: that is to say any strategy (no matter how it is defined) that solves this problem is equivalent to the solution explained here. I have discovered a truly marvelous proof of this, which this margin is too narrow to contain.

This was the riddle that led me to discover Ted-ed

this would work in theory, but of course there would be one or two people who aren't quite as bright as the rest of the group who would get confused and answer incorrectly

3:07 She hasn't been killed for looking behind

Most relatable part of this is us being at the front

As everyone can see the hat colour of next, first one will tell the hat colour of 2nd to 2nd an die but here 9 can be saved easily, why not like this ?

Highly logical and cooperative, huh? Can anyone see this actually working out?

Prisoner 10 sees no hats, so he answers blue. Everyone died. Don’t be prisoner 10.

It took me a little more than five minutes, but I got there...love this stuff.

i remember watching this when i was 7 as one of the first youtube videos i'd ever watched, first time being exposed to youtube, and i was in my parent's room since they were both gone that weekend, (i was home with my siblings and grandma) and i was alone. somehow, i was terrified after watching this, so it's kind of nostalgic rewatching this 6 years later

There’s absolutely no way a group of random people would accomplish this even if you explained the strategy

I wanna see the cows try and complete this test

I love how realistic this is. I would be at the front XD

I’m actually pretty happy I got the answer!

Before finding the answer: " Omg! this is impossible! " After finding the answer: "Omg! It was so easy! i am so stupeed!"

Why am I subconsciously thinking this is at any point in my life gonna be a useful strategy? Like im gonna be in a saw movie at some point or something

Oh my god, awesome, yet so complicated.

Plot twist: the cow in the end was worthier than everyone else and all humans were eaten anyway.

If only humans were this good at understanding plans

I'd be the one idiot to screw it up

100% going to warp this concept for my dnd game

Nice explanation. Helped alot

“You at the front of the line” Yo forget the puzzle is he calling me short!???!!

-Placed in a single file line facing forward in size order -Able to see everyone in front of you -May not: - Step out of line - Look behind you -Have either black or white hat assigned randomly -Must determine said color of high moving from back to front -No signaling whatsoever -Must have at least 9 correct. Using these requirements, you could simply just take your hat off and look at the color. It's not against the rules, and a guaranteed 10 correct.

I came up with another plan. Let me name the prisoners p1 to p10, p1 being the tallest and p10 being the shortest. P1 obviously can’t guess his hat colour. So he just says the colour of p2. Now p2 knows his colour. The strategy is, if p3 has the same color as p2, p2 just immediately says the color of his hat. Since the answer was immediate p3 knows that he’s wearing the same colour. But if p2 sees that p3 is wearing a different colour, he says his hat color after a long pause of 5 minutes. The pause meant that p2 and p3 aren’t wearing the same colour. So simple terms, P1 tells the color of p2 P2 now knows his colour If p3 is the same colour, he immediately says his colour If not, he takes a long pause of 5 minutes before he says his own color By paying attention to the timing p3 knows if his hat color is the same as p2’s

Another one is that everyone says the color of next person and has same result, its depend on first one any ways.

"our society forbids eating logical and co-operative creatures, but if you try to communicate with each other the colour of your hats, thus proving you are logical and co-operative, we will eat you" makes sense

Step 1: confirm you have green eyes. Step 2: ask the aliens to leave

Prisoner 10: accidentally counts the hats wrong

This is too good

one clumsy person like me...and you all are on alien buffet

if the aliens dont know english then why is the translator app written in english?

thats a neat puzzle

At 1:59 you introduced the criteria, after the pause. We had -information?

How to solve the riddle: *_step 1_* : confirm you have green eyes *_step 2_* : ask the alien to leave

if this was done with real people at least one of them would guess their hat was blue.

I came up with idea that each person says hat color of the person standing in front of him. So probability of the first guess is 50% and everybody else will be correct for sure. This plan is much easier to follow and to be understood correctly

Couldn’t you just alternate the first person says the hat in front of them, the second person repeats that color, the third person says the hat in front of them and so one. You’ll guess exactly 9 hats correctly

I'm the short one who forgets the plan and kills everyone.

Five minutes? Okay, here's the plan; there's ten of us, and three of them. We'll each go into three groups, and then when they get back, we attack them, steal their forcefield gun, and force them to let us go!

Last person tells the colour of the 2nd last persons hat ( Assume that 2nd last person is me) Strategy is if the next persons hat is of same colour I will call colour of my hat immediately else I will take 2 seconds pause and then call the colour of my hat. This will give the next person a silent signal about colour of his hat. The process continues till end of line. No signs, no intimation just a pause will do the trick

this channel is my love

Uhhhh. The horses name was Friday!

See how being short sucks.

Wow, the solution is so clever. Would not have thought of that, haha.

Well, now I will definitely be safe if aliens come and ask me such a riddle

Choose 10 people at random in America and I swear there's gonna be at least one that says green or some shit...