Can you solve the egg drop riddle? - Yossi Elran

  • Опубликовано: 7 ноя 2017
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    The city has just opened its one-of-a-kind Faberge Egg Museum, with a single egg displayed on each floor of a 100-story building -- and the world’s most notorious jewel thief already has her eyes on the prize. Can you help the thief formulate a plan that will drop the most expensive egg she can get safely into her waiting truck? Yossi Elran shows how.
    Lesson by Yossi Elran, directed by Artrake Studio.
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Комментарии • 5 084

  • TED-Ed
    TED-Ed  Год назад +598

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    • FOXTR0T1
      FOXTR0T1 29 дней назад

      I think you can do it in 7 tries by dividing the building into halves each time.
      Start by dropping from floor 50 if it doesn’t break focus on the top half of the building. Now go to floor 100 it breaks, now 75, it doesn’t, continuing down this halving route you can narrow down the floor after only 7 drops.

    • The Shipmaster
      The Shipmaster 3 месяца назад

      Idk why but your outro reminded me of Aperture Science from portal

    • Movie Miniac
      Movie Miniac 5 месяцев назад

      This trick can be pulled off using only 7 egg drops
      For an example
      First at 50 and if it breaks the next at 25 then if it breaks at 13 and if it survives at 19 then if it still survives at 23 if breaks then at 21 and if survives at 22. This can be applied for all circumstances. The logic is like Binary Search.

    • Doctor Shark
      Doctor Shark 6 месяцев назад

      There is another way to solve this first by a 1000 foot rope to repel on next go to the top floor and take the egg and repel down

    • hannah H-M
      hannah H-M 7 месяцев назад

      TED-Ed every 10 floor Interval if you checked every second floor it would still work the same first. Would it not? (Please correct me if I'm wrong) making the most 14

  • Wall2WallReno
    Wall2WallReno 9 часов назад

    Eggs thrown from 1 , 50 , 100 give you either 1-50 or 50-100 (assume a break at 50-100 ) then the zone should be split again at 25 (assume a break ) now 12th floor ( assume a break ) now 6th ( assume no break ) now 8th (assume no break ) now 10th assume a break .... therefore egg won't break at 11 or it will .....9 total tries no matter what and if the egg broke at the 50 drop you wouldn't even need the 100 therefore only 8
    I win

  • Alyssa Dewar
    Alyssa Dewar День назад

    I was just sitting here the whole time like “WHY ARE WE HELPING HER!”

  • K1naku5ana3R1ka
    K1naku5ana3R1ka День назад

    Great video as usual, but your segue into how the floor intervals can be different lengths was poor. I think you could have introduced the idea better by talking about how that worst possible number of 19 throws can only occur in the top group, because regardless of how many throws it takes to find the right interval, testing that interval can take up to 10 throws. Then, you can talk about how that might nudge you to try moving floors from the top intervals to the bottom, which can decrease the number of throws in those worst possible cases by moving extra floors to the lower intervals that can take them because their worst possible is way lower.

  • Ben Berkebile
    Ben Berkebile День назад

    The real question, what kind of idiotic guard wouldn’t be suspicious of even 1 egg falling from the tenth floor

  • Grande Gafanhoto
    Grande Gafanhoto День назад

    in the beggining, I thought in the floor interval solution too, but soon I figured that it would require too many tries, because you said that many tries could catch the guards attention

  • Nouche
    Nouche 2 дня назад +1

    If the thief can prevent death when she comes down with a rope, why not just steal the most valuable egg and take it with her on the rope?

  • Ngan Dinh
    Ngan Dinh 2 дня назад

    Why are we helping a robber?

    MAH TASTE IN MUSIC IS UR FACE! 3 дня назад

    Wouldn’t the egg become weaker with every drop meaning it becomes easier and easier to break

  • Brennan Perry
    Brennan Perry 3 дня назад

    Thanks for the tip

  • Gamer 4 life
    Gamer 4 life 3 дня назад +1

    Bish what egg breaks at a height of 20 cm. It would break at the 1st floor.

  • The6980
    The6980 4 дня назад

    why are we helping a thief?

  • Speedbun
    Speedbun 4 дня назад

    Answer: don't be a thief and get a goddamn job.

  • diana peebles
    diana peebles 4 дня назад

    Why didn’t she just put a cushion in the truck smh

  • shvartsmann yaakov
    shvartsmann yaakov 5 дней назад

    Who else dose not think at all and just listens to the answers at the end

  • AkashN 74
    AkashN 74 5 дней назад

    Why are we helping the thief?

  • Blob the dog with shoes on Brown
    Blob the dog with shoes on Brown 7 дней назад +1

    So, to drop the egg multiple times, she needs to go retrieve it, right? That means she has to go all the way down to the ground floor and all the way back up with the replica. So, why can she do that, but not just carry the egg she wants to steal down the stairs?

  • Arcticx369
    Arcticx369 8 дней назад +1

    Here’s an idea..

    *Don’t rob an egg museum*

  • 3vilboy06
    3vilboy06 8 дней назад

    Just put a bunch of pillows. Boom solved

  • Nicolás Pinto
    Nicolás Pinto 9 дней назад

    How can we prove that there's no way to test it with fewer trials?

  • Xtri 9
    Xtri 9 9 дней назад

    Wait but why am I helping a robber

  • Fish Biscuit
    Fish Biscuit 10 дней назад

    Why not just get a dozen pillows in the trunk where the 100th egg would go?

  • W J
    W J 10 дней назад

    Uh... why would the thief want to steal a egg? In the beginning, they said the thief was a jewel thief. Then why don’t the thief just steal the jewels?

  • Marlon Viana
    Marlon Viana 11 дней назад

    A forma que eu conheço é: dividindo a distância na metade à cada jogada de ovo, 50,75,87,
    Vamos supor que a altura máxima seja 74 andares sem o ovo quebrar, no 75° quebra. Eu começaria jogando o 1° ovo na metade do prédio
    100/2=50, o ovo não quebrou, então vai 50% mais alto
    50+25= 75° andar
    O 2° ovo Jogaria do 75° andar, ele quebraria. Então teria que descer alguns andares.
    100-75= 25
    25/2= 12.5 -> 12 (arredondado, para menos ou para mais, tanto faz)
    75-12= 63°
    3° ovo no 63° andar. Ele não quebraria. Então vai até o 63° andar sem quebrar, mas não vai mais que o 75° andar, ou seja, está entre 63 e 75. Vamos continuar com a metade da diferença dos dois andares.
    75-63= 12
    12/2= 6
    63+6=69° andar
    4° ovo não quebraria, pode ir mais alto.
    75-69= 6
    69+3=72° andar
    5° ovo no 72° andar
    6° ovo no 73° andar
    7° ovo aguentaria o 74°.
    Então em 7 ovos podemos achar a resposta.
    O maior número de ovos que eu precisei para encontrar a resposta com essa técnica foi 8 ovos num prédio de 100 andares, se o ovo não quebrar até o 100° andar precisaria de 8 ovos para encontrar a resposta

  • LOLSflint
    LOLSflint 11 дней назад


  • Annabeth Chase
    Annabeth Chase 11 дней назад +1

    here, use this when dropping the egg at the top :)

  • France’s Loving Fangirl
    France’s Loving Fangirl 11 дней назад

    The answer is JESUS

  • Luke Boss 78
    Luke Boss 78 12 дней назад

    Why doesn’t she just put a mattress or something soft at the bottom to break the egg’s fall?

  • janhavi kolambe
    janhavi kolambe 13 дней назад

    At 3:23 what do you do if it does not break on the 9 the floor
    It can either be the ninth floor or the 10th floor also

  • Jerry H Reitsmax
    Jerry H Reitsmax 13 дней назад

    Is this the instagram egg!??

  • Ryan Cox
    Ryan Cox 13 дней назад +1

    It can actually be done in 7 throws if you are okay with breaking the eggs since it would only be an extra $75 dollars (if all eggs broke) to throw 7 less eggs of the roof since the guards would obviously notice a person throw 14 eggs off of a building. This is how you do it, from floor 50, you throw it, if it breaks you move down, if it doesn’t you move up by 25, then up or down by 13, then 6, then 3, then 2, then 1. If the last one breaks it is the floor below, if it does not it is that floor.

  • Nick H. Nguyen
    Nick H. Nguyen 14 дней назад


  • Siddhant Dandotiya
    Siddhant Dandotiya 14 дней назад

    Why am I supposed to help her with stealing something?

  • Keheck
    Keheck 14 дней назад

    Why didn't she just fill the truck with soft things that soften the fall

  • Rusty Orange
    Rusty Orange 15 дней назад

    Wouldn’t the egg be more damaged so it would destroy on different floors giving it a weak shell from previous drops

  • ROBO
    ROBO 15 дней назад

    If I drop at floor 50 and it breaks then I go to 25. Still breaks so I go floor 13. Breaks at 13 then I go 7. If it's not 7 then 8-12 if it doesn't break at 7, or 1-6 if it does break at 7. If I keep splitting the number in half I keep getting max of 10. What am I missing? Same would apply if it didn't break and I went up.

  • VelociforceGaming
    VelociforceGaming 15 дней назад

    Why not just repel down with the top floor egg?

  • Zuhairi Hassan
    Zuhairi Hassan 15 дней назад +1

    If I brought replica eggs into the egg museum, the guard will think I already stole an egg.

  • Good Goat
    Good Goat 16 дней назад

    1:32 *that she FIND*

  • Nishit Shah
    Nishit Shah 16 дней назад

    I came up with 100/n + n-1 for trial and error. Now crying in the corner!

  • Sale Volcano
    Sale Volcano 18 дней назад

    I'll just settle for 5th or so

  • Nate Playz
    Nate Playz 18 дней назад

    thief: *throws eggs out windows 14 times*
    guards: *don't notice*

  • Anthony Rogers
    Anthony Rogers 19 дней назад

    There is a better way of doing this that requires less eggs and computer science uses this same way to flow through data.

  • Keith Mathew Castro
    Keith Mathew Castro 19 дней назад

    Why would i help a theif?

  • christian cowles
    christian cowles 20 дней назад

    I disagree with this answer (assuming I understand the problem correctly). If each egg were doped half way between a known good and bad distance, then the number of regions explored would increase as 2^n, and 100 regions could be explored within 7 drops. That is, the first drop would determine if the critical height is above or below the 50th floor, the second would determine if the critical height was above or bellow either the 25th or 75th floor, etc.
    This was fun problem. Thanks for making this video.

  • Aysha Zahra
    Aysha Zahra 20 дней назад

    Just sell the replicas to some shady guy or bribe the guards

  • bigfoot sandwich
    bigfoot sandwich 21 день назад +1

    I forgot that if an egg survived, you can do it again. >:(

  • Dalton Matlow
    Dalton Matlow 21 день назад

    She could go to another 100 stori building

  • Marc Lim
    Marc Lim 22 дня назад

    I would give up since wind conditions and other variables could throw the egg off course and break it.

  • Emaad Zaheer
    Emaad Zaheer 23 дня назад

    Just pillow the bottom of the van

  • Boss Girl Awesome
    Boss Girl Awesome 23 дня назад

    Why are we helping her if she's thef

  • Ejwkksk Djwksm
    Ejwkksk Djwksm 23 дня назад


    *Go down WITH the egg*
    Is it that hard?

  • Bumstickle _
    Bumstickle _ 24 дня назад


  • NineLivesx5
    NineLivesx5 26 дней назад

    Or she just get some padding I got the truck and get a good aim

  • h2j here
    h2j here 26 дней назад

    If she could walk in with a replica egg then why can't bring the most expensive egg same way

  • Itz_Poof
    Itz_Poof 27 дней назад

    But dosent the eggs get weaker every drop?

  • Mcs23
    Mcs23 27 дней назад

    wait if her plan is to throw the egg to her truck and to repel down after, can't she just repel down with the egg?

  • Nox-inese Nexitanese
    Nox-inese Nexitanese 28 дней назад

    *10/10 Theif model*

  • Bill
    Bill 28 дней назад

    Can't you get it in 6 drops?
    1. start at 50
    survives: go up 25 floors (floor 75)
    breaks: go down 25 floors (floor 25)
    2a) Drop at 75
    Survives: Go up 13 floors (floor 88)
    breaks: go down 13 floors (floor 62)
    2b) Drop at 25
    Survives: Go up 13 floors (floor 38)
    breaks: go down 13 floors (floor 12)
    3a) Drop at 88
    Survives: Go up 7 floors (floor 95)
    breaks: go down 7 floors (floor 81)
    3b) etc etc
    Basically the increments being 50, 25, 13, 7, 4 and 2
    Ex: 50>25>38>31>35>33>

  • MegaCoolbruh
    MegaCoolbruh 28 дней назад +6

    What you do:
    1. Put cotton balls into two cups
    2. Put the 100th floor egg into one of the cups
    3. Duct tape the cups together
    4. Get a box
    5. Fill it halfway with cotton, newspaper, and other things like that
    6. Put the egg cup into the box
    7. Repeat Step 5 until the box is full.
    8. Duct tape the box shut.
    9. Rip open fifty shopping bags so they are flat.
    10. Connect the bags with duct tape.
    11. Connect this bag parachute to the box using string wrapped in a couple layers of duct tape.
    12. Shove it through the window.
    13. Repeat as much as you can.

  • EpicFaceGamer/Roblox
    EpicFaceGamer/Roblox 28 дней назад

    The eggs sound like roblox to get the eggs from the egg hunt

  • Lucas Magalhães Luciano
    Lucas Magalhães Luciano 28 дней назад

    Why 14 drops ?
    (1) floor 50
    (2) floor 75
    (3) floor 87
    (3) floor 93
    (4) floor 96
    (5) floor 98
    (6) floor 99
    (7) floor 100
    for this can be tested in ever floor just halfing the height. . .

  • Jake Paul
    Jake Paul 29 дней назад

    There’s a thing called backpacks put the egg in there then use the rope to get down

  • StevenLikesPizza
    StevenLikesPizza 29 дней назад

    I have a solution: Get a job.

  • Jacob Schultz
    Jacob Schultz 29 дней назад

    And I thought game theory blew up my mind

  • logan shilds
    logan shilds 29 дней назад

    creates mini parachutes

  • Baplo B
    Baplo B 29 дней назад


  • Lokesh Singh
    Lokesh Singh 29 дней назад

    How about binary search? We can get the answer in only 7 attempts.

  • Quinton15117
    Quinton15117 29 дней назад

    Can’t I just put an pillow in the truck? Like a big big pillow.

  • Dziecko Minecraft'a
    Dziecko Minecraft'a Месяц назад

    Not 14 from 7 to 9 , drop on 100. floor breake divide by 2 drop on 50. floor or if it not brooke 50+25 drop on 75. floor and again.

  • Hex
    Hex Месяц назад

    all comments are either:
    "i can do it 7, because i misread the rules"
    "why don't you just repel down with the egg"
    "14 eggs is a lot of times, the guards would notice"
    "just put pillows in the truck"
    or someone doing science and thinking they solved the riddle.

  • Hex
    Hex Месяц назад

    if you can get away with dropping 14 eggs out the window, why don't you just steal 14 eggs?

  • jose casillas
    jose casillas Месяц назад

    It was a bad riddle. That the guard would notice if you threw too many of them was too vague, imposing some sort of arbitrary and ambiguous limit to the number of eggs thrown. Second, one of the rules clearly stated that you only had TWO replica eggs that you could only use ONCE each, unless you used the real ones as test dummies as well. Otherwise, 14 tries? Wtf? I wish they would have just made a video explaining the equation.

  • Twelve Midgets
    Twelve Midgets Месяц назад

    Jokes on you i use pillows

  • Sookhyun Nam
    Sookhyun Nam Месяц назад

    if you first try with the 50th floor and if it breaks try 25 if it breaks again try 13 or 12 if it breaks again try 6 and if it breaks again try 3 if it breaks again it has to be 1 or 2 meaning you will only need 7 tries most

  • Edwards top 10
    Edwards top 10 Месяц назад

    Your a criminal you don’t care about guards

  • Olivia Thompson
    Olivia Thompson Месяц назад

    If she is a notorious thief why is she even allowed in the building at all?

  • Andy Sun
    Andy Sun Месяц назад

    Why can’t you put something soft in your truck

  • josh acuna
    josh acuna Месяц назад

    I ended up with a method that takes 8 tries everytime after trying to solve this puzzle. Maybe not a better answer but it certainly is a more consistent alternative

  • Pallav Panwar
    Pallav Panwar Месяц назад

    This is not the least no. Ypu can do this in 7 tries by using the half mesthod. First drop from 50 if breaks then from 25 if again braks then from 12/13 if it doesnt then from 37/38 and appling same method it would take a maximum of 7 attempts. Best try yourself by picking any no. And try the method.

  • Aman Khatkar
    Aman Khatkar Месяц назад

    why don’t we just bring some straws and do the egg drop thing we do in school.
    Make a triangle out of straws, place egg in middle have starts passing by the sides of the egg so the force passes by the egg. Boom! Now theres no need to drop the egg 19 times, and go to jail!

  • Davi Dubeux
    Davi Dubeux Месяц назад

    I think it might be able to solve in at most 7 tries, we can start at the middle and keep dividing and we can go through the worst case cenario so we have no doubt. Starting at the 51 floor and it breaks we have 50 more floors, 26 floor and it breaks more 25 floors, 13 floor and it breaks more 12 floors, 7 floor and it breaks 6 more floors, 4 floor and it breaks 3 more floors, 2 floor and it breaks 1 more floor and its done. Same way can work assuming it don't break in previous tries. Making a total of 7 attempts.

  • Daredevil I.T.
    Daredevil I.T. Месяц назад

    i got the riddle

  • Darrel Jones
    Darrel Jones Месяц назад

    I'm pretty sure fewer than 100 Faberge eggs were made in total, but otherwise, not a bad problem.

  • Riccardo Spadini
    Riccardo Spadini Месяц назад

    Very nice riddle!

  • Matthew Barnes
    Matthew Barnes Месяц назад

    Get the most valuable egg and then climb down into your getaway van

  • Chuck Joe
    Chuck Joe Месяц назад

    How does she get back down and back in

  • Aleena Hafiz
    Aleena Hafiz Месяц назад

    So if your in a museum, why would they let you open the window?

  • 10k subs with no Videos
    10k subs with no Videos Месяц назад +1

    Can’t she just hold it while going down

  • Vladyslav Hryhorenko
    Vladyslav Hryhorenko Месяц назад

    the correct answer is: i wouldnt help a thief

  • Tataro Toda
    Tataro Toda Месяц назад

    Wouldn't dropping the egg make its durability decrease gradually as each floor you drop? Like if you drop the egg at ex. 10th floor and it already breaks after you've dropped it several times in each floor but what if it breaks because its already sturdiness is already weakened and who knows it wouldnt break after its first fall on the 10th floor or higher?

  • Shikha Sinha
    Shikha Sinha Месяц назад

    Coudn't she just stuff her truck with feathers or soft toys or pillows

  • Niraj Kumar
    Niraj Kumar Месяц назад

    You could have used binary search hear for the best result

  • Archie Gray
    Archie Gray Месяц назад

    I enjoyed it but I dont understand it

  • Ivy Lmoa
    Ivy Lmoa Месяц назад

    In computer science I learnt about binary search which is a searching algorithm in which divides the array of numbers in half and keeps on dividing by half til it gets to the number you’re looking for. We were writing code for this and what we would have to do is guess the number the computer thinking of from 1-100 start at 50 the computer will tell us if it’s too low or too high. Too high then we would start at 25 too low we’d start at 75 and would keep carrying on til we got it. I suppose it might work for this too. I believe the most guesses you would get is about 6 or 7

  • Boss Girl Awesome
    Boss Girl Awesome Месяц назад

    Why should we help her anyways, because she is a thef

  • DeadGuests
    DeadGuests Месяц назад

    Can somebody remind me why we’re helping a freaking *jewel thief* steal *eggs* ?!

  • Jackson Reed Sweet
    Jackson Reed Sweet Месяц назад

    She could shimmy down with the egg in her hand or in a bag. She's a great cat burglar, so it shouldn't be that hard.

  • Matthew Smith
    Matthew Smith Месяц назад

    What laid the eggs?