# Can you solve the locker riddle? – Lisa Winer

Your rich, eccentric uncle

just passed away, and you and your 99 nasty relatives have

been invited to the reading of his will. He wanted to leave

all of his money to you, but he knew that if he did,

your relatives would pester you forever. So he is banking on the fact that he taught you everything

you need to know about riddles. Your uncle left the following

note in his will: “I have created a puzzle. If all 100 of you answer it together,

you will share the money evenly. However, if you are the first to find

the pattern and solve the problem without going through all of the leg work, you will get the entire inheritance

all to yourself. Good luck.” The lawyer takes you and your 99 relatives

to a secret room in the mansion that contains 100 lockers, each hiding a single word. He explains: Every relative is assigned a number

from 1 to 100. Heir 1 will open every locker. Heir 2 will then

close every second locker. Heir 3 will change the status

of every third locker, specifically if it’s open,

she’ll close it, but if it’s closed, she’ll open it. This pattern will continue until

all 100 of you have gone. The words in the lockers that remain

open at the end will help you crack the code for the safe. Before cousin Thaddeus can even start

down the line, you step forward and tell the lawyer

you know which lockers will remain open. But how? Pause the video now if you want

to figure it out for yourself! Answer in: 3 Answer in: 2 Answer in: 1 The key is realizing that the number

of times a locker is touched is the same as the number of factors

in the locker number. For example, in locker #6, Person 1 will open it, Person 2 will close it, Person 3 will open it, and Person 6 will close it. The numbers 1, 2, 3, and 6

are the factors of 6. So when a locker has an even number

of factors it will remain closed, and when it has an odd number of factors, it will remain open. Most of the lockers

have an even number of factors, which makes sense because factors

naturally pair up. In fact, the only lockers that have

an odd number of factors are perfect squares because those have one factor that when

multiplied by itself equals the number. For Locker 9, 1 will open it, 3 will close, and 9 will open it. 3 x 3=9, but the 3 can only be counted once. Therefore, every locker that is

a perfect square will remain open. You know that these ten lockers

are the solution, so you open them immediately

and read the words inside: “The code is the first five lockers

touched only twice.” You realize that the only lockers

touched twice have to be prime numbers since each only has two factors: 1 and itself. So the code is 2-3-5-7-11. The lawyer brings you to the safe, and you claim your inheritance. Too bad your relatives were always

too busy being nasty to each other to pay attention

to your eccentric uncle’s riddles.

Unbelievable

I had watch this video 2 times to understand question…….☺😅

1…1 + 0101…01 + 001001…001 + … + 000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000001. = x1 x2 x3 x4 … x100 : if x is even, it is closed, and if it is odd, it is opened.

In a general rule, numbers can be factored as a product of primes:

n = (p1^e1)×(p2^e2)×(p3^e3)×…×(pk^ek), where pz is a prime number (z = 1, …, k) and ez is the exponent of it. Supposing that z ≠ i implies that pz ≠ pi, we have that, the number of divisors of n (I'll treat it as a function D(n)) is equal to:

D(n) = (e1 + 1)×(e2 + 1)×(e3 + 1)×…×(ek + 1)

So we have that:

Theorem 1.1:

If, and only if, 2 | D(n), then the box of number n is closed.

That is to say that all of the boxes of number n = (p1^e1)×…×(pk^ek) are such that ez is even for all (z = 1, …, k).

So the boxes open are:

Number of the box:

2², 2⁴, 2⁶;

3²,3⁴;

5²;

7²;

And the combinations of that numbers:

2²×3²

2²×5².

I probably committed some serious English syntax and grammar errors, but at least, I guess that I won a prize of my uncle.

Did birth control not exists when my parents gave birth to 100 of us

Because my uncle taught me. Easy

I was expecting a very different riddle This was more of a math class and math + me = 🙁

idk

Pretty sure we got this question, but simpler, in advanced math. Seems legit. 🙃

What a minute what was that the two last numbers in the code seven eleven!?

OMG I'm early to another amazing video!?

39 clues plotline, is that you?

🙂 The code is only prime numbers. I know prime factorisation.

Ive spent over 3 hours and gone through two full notebooks of scrap paper trying to solve it and basic math was the answer. Im done and im just gonna go to sleep.

If this was me, my uncle would have face palm in the heaven.

What if there are a million prisoners? That means where they have to wait for 2739 years. Good luck.

With this kind of intelligent you must be able to protect yourself against all these greedy relatives

I can't be the only one who doesn't get it. Right?

Please?

he could’ve just told you the answer before he died wtf

i feel like i have brains

After you get all the money your relatives will still pester you about giving them money so the uncle still faces the same problem

I really do have 2 functioning brain cells.

Wait shouldn't the numbers be 1 2 3 5 and 7 since 1 is a prime number

plot twist: the relatives are extremely smart!!

Who always pause the video but never get answer?😂😂😂

no i cant

This is bootleg 39 clues

“One does not complain while the other side plays the game” -harvey specter

We did this in Math class and it was a math problem but the only numbers that I know are open are 1, 4, and 9

what if you're bad at math?

This is really cool

If I worked on it for only a few more minutes I feel like I could've solved it. I didnt notice perfect squares are all open but I figured everything else out oof. I'm disappointed in myself lol

And when you walk away with the prize, all your relatives will STILL pesture you, because people are greedy, making the entire riddle pointless.

WELL I guess I’m not getting the inheritance

Dont mean to flex but this was on a math test for my grade and out of three people i solved it so uh….

Big brain

First ted riddle that I was able to solve by myself.

i cannot believe i solved it. Dayum!!

Not that hard…..sikes

I like how all of these have stories to it

This is the only Ted-ED riddle I solved on my own.

Me: I know which locker will remain open

Lawyer: Really?

Me: Nah just kidding…I don't know…

KHA!?

Still dont get it

Nah i get it now.

With these kind of riddles you always have to realize something really specific. I feel like a lot of people wouldn’t realize that specific thing. That’s why I don’t like riddles. But these videos are really fun to watch anyway 🙂

Would they not harass you for money even if you hadn’t been specifically named the sole heir? This makes no sense.

She is number one and sees the notes in the numbered lockers so she opens them and voila she wins

The Uncle must le the Riddler

I acctially had an extra credit on a test on this except for a thousand lockers we got an extra day to do the extra credit!

I still dont get it🤣

That grandfather is a good grandfather

No

At my funeral, ima play crab rave.

DarthLazy

—————-

Is Gone!!!

Didnt understand anything but thats a nice riddle

Big brain

It's just like The 39 Clues………sort ofI like ted ed videos but they are too chill its kinda depressing

I must be the favourite child then

JAMES GRIME (SINGINGBANANA) ALREADY FIGURED THIS OUT YEARS AGO

The real riddle is how are 99 of your relatives still alive

AHHH!! MATH!! MY WEAKNESS MATH!!

DIES수포자는 안된다?

Does writing a few lines of code to solve this count?

Mah uncles are normal

Also I love the lawyer voice :>

MY GOD I JUST CANT UNDERSTAND ANYTHINGGGGGG

問題と解答を見ても何を言ってるのか分からない。。。

so, ten lockers are open

I did figure it out myself and it was literally the first number theory problem that I enjoyed solving. They all sound boring and mysterious at the same time!

Wait…… what?

taking a wild guess…the uncle didnt specify if the first person should get the correct answer but just answered first, so I get the inheritance simply because I answered first

the info is not sufficient

Well 3 seconds seems pretty long time🙄But how? Because you’re smart

What I do

99 RELATIVES!!!

Why were there so many question marks the girl was following?

What if the character was shown in the video to be a young child and sucked at math

😊😊😊

I like this vid i already sub to ted ed if you also like this vid pls like this comment uwu

So Basicly my Uncle thought he should be a smartass iven after his death Well Im sorry I didn't know I was around a profesional

Easier awnser:Play Justin Bieber Baby and evryone Will die of ear bleeding

good ol' thaddeus

Bruh she’s like 6 how the heck did she figure that out

I think for hours and was shock when the solution was just like that

What an amazing riddle

We did this in math class and I actually got it, I feel like I can now answer the laws of the universe and summon Jesus in the process.

0:42 Different Voices!

YAAAY!It gave us a bonus riddle at 3:12

Wont they still pester her

How The Grand Budapest Hotel should have ended

brain.exe stopped working

This is the plot of “39 clues”😂

Soooo… her uncle taught her how to be a math whiz instead of answering riddles…bc there’s no way she did all that before someone stepped up to begin. She knows her uncle and his “riddles” way better than anyone else.

And then you realise , your uncle is poor !!

At the end, you’d still take all the inheritance, and they’ll still pester you

He said that the first person would open every locker. He never the first would close lockers. The first will go one more time than the second and third, so when the 100th person goes they will also open every locker. Every locker would end up being open. They make the rules too vague in these videos.

I spent 1 hour straight trying to solve it in Paint . By adding objects to the locker then if the number was odd, it was supposed to be open. Well guess I did some mistakes in the process but anyway it was fun. Here is my work https://prnt.sc/pff2sl

1. Confirm you have green eyes

2. Claim the money

but then you realize that only prime number squared has only 3 factors

RIP

but then you realize that it said ODD numbers not 3 factors

RIP

I DONTO ANDERUSUTANDO

I actually solved it in few 🙂

That's what I'll do when I make my will. A riddle contest.

If I’d been one of those relatives and watched them figure it out so fast I would have just assumed they were told the answer before he died, at which point they would probably still endlessly harass her for the money

Me: (solves riddle)

Relatives: (get angry and are about to fight me)

Me: FML.