Three Dice Trick - Numberphile

Ғылым және технология

Ben Sparks with another trick - can you guess how it works before he explains it?
More links & stuff in full description below ↓↓↓
This is the second of a trilogy of dice tricks with Ben Sparks... More to come...
Martin Gardner called this trick "Guessing The Total".
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Пікірлер: 491

  • @SeanHodgins
    @SeanHodgins2 жыл бұрын

    All tricks are usually simple, its obfuscating the simplicity that makes it cool. This one is very cool.

  • @iwersonsch5131

    @iwersonsch5131

    2 жыл бұрын

    Not really, there are some complicated card tricks where the deck ends up shuffled in an unexpected way. See for example Matt Parker's video on a perfect Bridge deal.

  • @Vlow52

    @Vlow52

    2 жыл бұрын

    You clearly not familiar with trick construction. Self-working and semi-automatic tricks are simple, but at the most, it uses a years of sleight of hand practices and presentational refinement to make it less obvious for a lay person.

  • @jama211

    @jama211

    2 жыл бұрын

    @@Vlow52 or you're over thinking their comment a little

  • @BinaryBolias

    @BinaryBolias

    2 жыл бұрын

    Less obfuscated if you use a radix seven numeral system.

  • @seshamohansrivatsavamaddal1160

    @seshamohansrivatsavamaddal1160

    2 жыл бұрын

    Obfuscating.... Hmmmm

  • @martinfladby6158
    @martinfladby61582 жыл бұрын

    I like that this video is 7 minutes long

  • @wobblysauce

    @wobblysauce

    2 жыл бұрын

    magic.

  • @brumd

    @brumd

    2 жыл бұрын

    That definitely means it has been edited down from 14 minutes.

  • @abnatian

    @abnatian

    2 жыл бұрын

    Long(er) than expected I'd say, regarding the usual audience.

  • @Triantalex

    @Triantalex

    5 ай бұрын

    ??

  • @capfer77018
    @capfer770182 жыл бұрын

    Regarding the non-reversible dice (d8), some dice are designed to have subsequent numbers next to each other. These are generally called spindown dice, and are used when the dice is needed to represent some value that needs to be changed often. Having subsequent numbers next to each other makes that easier, and they are still sufficiently random. The main use is a d20 for life totals in Magic the Gathering.

  • @Daspletophysis

    @Daspletophysis

    2 жыл бұрын

    The d8 shown in this video can’t be a spin down dice because consecutive numbers are on opposite faces

  • @joaopaulomendonca1414

    @joaopaulomendonca1414

    2 жыл бұрын

    In addition, d8 are usually done in a way that oposite pair of faces sum the same values as the pair of faces in the other side of the dice. If you look to any 4 faces view of the dice, this faces are suposed to sum up to 18. Some nice dice tricks can come from this also =P

  • @Daspletophysis

    @Daspletophysis

    2 жыл бұрын

    But it is well balanced in the sense that each set of four numbers that share a vertex sum up to 18

  • @yuvalne

    @yuvalne

    2 жыл бұрын

    +

  • @X_Baron

    @X_Baron

    2 жыл бұрын

    There's probably some dice randomness paper somewhere that can explain why the "vertex sum" of 18 is better than any arrangement with the consistent opposing sides sum.

  • @Pablo.Rodriguez
    @Pablo.Rodriguez2 жыл бұрын

    This may be the first time I got the trick before the explanation. And now I'm so happy :)

  • @Eggnog18

    @Eggnog18

    2 жыл бұрын

    You and me both! I feel so smart, even though I blank at most of the other videos. lol

  • @wayoutdan8334

    @wayoutdan8334

    2 жыл бұрын

    same here

  • @Triantalex

    @Triantalex

    5 ай бұрын

    ??

  • @AldrichNaiborhu
    @AldrichNaiborhu2 жыл бұрын

    These types of magic tricks are the ones that, at first, looks very impressive! But when we dig deeper, turns out to be much, much easier than I thought. It's still cool though!

  • @bobby_tablez

    @bobby_tablez

    2 жыл бұрын

    I would say most magic tricks are that way. Unless they involve some really technical sleight of hand, you need only be told where the misdirection was, then it seems easy.

  • @adarshmohapatra5058

    @adarshmohapatra5058

    2 жыл бұрын

    @@bobby_tablez Exactly. That's why a magician never reveals their secret. Otherwise the magic doesn't feel as impressive anymore and people start thinking, "I could have done that!".

  • @pugnaska

    @pugnaska

    2 жыл бұрын

    @@bobby_tablez yep, i dont know how to do magic, but love to see it, and its always funny how people come up with complicated solutions to do a trick, when is always the simplest thing

  • @nosirrahx

    @nosirrahx

    2 жыл бұрын

    I instantly got it because I have played probably 500 games of Parcheesi. Using the top and bottom of the dice when you get doubles is part of the game so I already know about the "always 7".

  • @Triantalex

    @Triantalex

    5 ай бұрын

    ??

  • @fast-eddie-clarke
    @fast-eddie-clarke2 жыл бұрын

    thanks for all the free beer I'm gonna get at the pub now

  • @reidflemingworldstoughestm1394

    @reidflemingworldstoughestm1394

    2 жыл бұрын

    You could build "difficulty" by setting up the first round so that you know which one was rolled twice, then on the next round you tell your victim that you will sacrifice this knowledge to >koff< make it harder on yourself.

  • @jenakuns

    @jenakuns

    2 жыл бұрын

    You say that but it would require the person to add at least 5 numbers together correctly, which definitely won't be guaranteed a couple drinks in.

  • @Triantalex

    @Triantalex

    5 ай бұрын

    ??

  • @sephalon1
    @sephalon12 жыл бұрын

    The top and bottom of a 6-sided-die always total to 7. There. That's like 95% of dice tricks.

  • @dermaniac5205

    @dermaniac5205

    2 жыл бұрын

    And most of us learn that as children

  • @scottllewellyn8221

    @scottllewellyn8221

    2 жыл бұрын

    yeah I was gonna say surely it's not that hard... I figured it out straight away

  • @cybersoul3371

    @cybersoul3371

    2 жыл бұрын

    @@scottllewellyn8221 to be fair, they had the dice addition showing on the screen and in the moment without that visual aid, it would've been harder to figure out

  • @scottllewellyn8221

    @scottllewellyn8221

    2 жыл бұрын

    @@cybersoul3371 mate it’s simple arithmetic where the highest number is 6… with or without visual aid, the math was the easy part. but it’s not hard to work out regardless

  • @okaro6595

    @okaro6595

    2 жыл бұрын

    I knew that but I still did not get it until it was explained.

  • @RedStinger_0
    @RedStinger_02 жыл бұрын

    Brady's gasp was precious.

  • @hyfy-tr2jy
    @hyfy-tr2jy2 жыл бұрын

    Always love new videos from the resident "Maximus the Mathematician". You have to admit he looks like Russell Crowe

  • @WetBanditYGO

    @WetBanditYGO

    2 жыл бұрын

    Lol I was just thinking that!

  • @Triantalex

    @Triantalex

    5 ай бұрын

    false.

  • @gx_no
    @gx_no2 жыл бұрын

    Its amazing how it comes together all of a sudden. As soon as he said at 2:35 that adding 7 to the sum of the number gives the final number, it all clicked into place for me.

  • @viliml2763

    @viliml2763

    2 жыл бұрын

    As soon as he said at 0:07 that he had a blindfold, I knew what the trick was going to be.

  • @jacobkaneff8261

    @jacobkaneff8261

    2 жыл бұрын

    I can't believe he got the 7 trick, but then couldn't figure it out. Because I had no idea how he was doing it until he told me opposite ends add to 7, but then it became obvious. But these things on the camera is more pressure!

  • @adamsbja

    @adamsbja

    2 жыл бұрын

    For me as soon as he brought the bottom of the die into play I was watching for it. Once you know that fact about 7 most of these fall apart if you're going into them with a puzzler's mindset.

  • @nav5738

    @nav5738

    2 жыл бұрын

    @@viliml2763 As soon as I saw the video title I knew what the truck was going to be

  • @marc0s158
    @marc0s1582 жыл бұрын

    Only mathematics and TTRPG players have those dice. Im thinking he is both

  • @livedandletdie

    @livedandletdie

    2 жыл бұрын

    CCG and TCG players as well, Dice are important. I have D20s D12s D8s D6s D4s and I have D2s D3s D5s D7s D9s D10s D11s etc as well. You might wonder how those dice could be fair... but D2s are easy you just have a D6 and the numbers 1,3,5 are 1 and 2,4,6 are 2. D3s are 1,4 for 1, 2,5 for 2, and 3,6 for 3. D5 now that's an interesting dice, it's a D6 but the 6 is reroll. D7s now we're into complicated Bullcrap, it's a fair D8 with 8 being a reroll, D9s is the same with a D10 dice, sure it's not a fair dice to begin with, but still. D11s are D12s with one side being reroll. However for higher rolls than that, Using Pseudo-random number generators are way better, after all, using dice isn't exactly fair in the first place, it only takes 2 hours of practice to roll a single dice to any digit of choice, consistently.

  • @jansenart0
    @jansenart02 жыл бұрын

    OR, a simpler explanation, is that he's a WARLOCK

  • @feraldreams7978

    @feraldreams7978

    2 жыл бұрын

    Dungeon Keeper intensifies!!

  • @illusionist1872

    @illusionist1872

    2 жыл бұрын

    His patron is Michael Stevens

  • @jansenart0

    @jansenart0

    2 жыл бұрын

    @@illusionist1872 A suspiciously normal name.

  • @illusionist1872

    @illusionist1872

    2 жыл бұрын

    @@jansenart0 Vsauce. I was referring to Vsauce.

  • @oafkad
    @oafkad2 жыл бұрын

    This is so cool. I can't get over how much I like it.

  • @Matthew-bu7fg
    @Matthew-bu7fg2 жыл бұрын

    i'll be using this one on my students. Great video!

  • @KarlHamilton
    @KarlHamilton2 жыл бұрын

    Brilliant, cheers for this :)

  • @ZachGatesHere
    @ZachGatesHere2 жыл бұрын

    If you're familiar with dice enough to know about the relationship between opposite sides this is one of those times where you can feel all smart and go "I know how he did it!"

  • @lukehawksbee

    @lukehawksbee

    Жыл бұрын

    I'm familiar enough with dice that I guessed what the trick was going to be before I even started watching the video, just from the thumbnail. I'm surprised that the guy trying to work out how it works takes so long after stating that opposite sides add up to 7-I would have thought it should be immediately obvious if you know that.

  • @camdix3250
    @camdix325011 ай бұрын

    This is fantastic! It is the first time I have seen any of your videos. I'm a 66 year old retired school teacher. You are a brilliant teacher - clear, concise and very interesting to listen to. Your manner, style and presentation are so very engaging. This would be fantastic for teachers to use in the classroom with their students - and the students can then go home and enjoy fooling their parents. Thank you so very much for bringing us this video. I just subscribed.

  • @dragoda
    @dragoda2 жыл бұрын

    As usual, this channel is amazing.

  • @AMorphicTool
    @AMorphicTool2 жыл бұрын

    My favourite is still the card trick I saw on here some time ago. A cool use I found for it was very quickly checking if I have a complete deck as the trick doesn't work without one. This is a fun little trick though, definitely going to use it.

  • @raedev
    @raedev2 жыл бұрын

    oh my god my dad used to do this trick ages ago when i was like 9 at family reunions and i had completely forgotten about it until now

  • @vsm1456
    @vsm14562 жыл бұрын

    I love videos with Ben! Please do more. :D

  • @snatchngrab8262
    @snatchngrab82622 жыл бұрын

    It's the "do you remember what happened in the middle" part that is the actual magic.

  • @FogToo
    @FogToo2 жыл бұрын

    I think that d8 is a roll down dice used for MtG and RP games for health totals and such. Comes in various configurations. You can also get them as "normal" dice as well.

  • @IIARROWS

    @IIARROWS

    2 жыл бұрын

    If they come in a different configuration then the correct one, they are considerate loaded. Every die must keep the 1+n on opposite sides, and growing in a specific direction. In a d20, 2 must always be near 20 and 18, which must be near 4 and so on. Probably is for ignorance of the manufacturer, and that comes from cheap dice.

  • @Caribbeanmax

    @Caribbeanmax

    2 жыл бұрын

    @@IIARROWS spin down dice aren't made for rolling, they are meant to keep track of numbers and in that case you want consecutive numbers next to each other for ease of use this has nothing to do with ignorance, they are just made for another use case

  • @IIARROWS

    @IIARROWS

    2 жыл бұрын

    @@Caribbeanmax OK, when have you ever seen d8 or d12 sold for spin down? I only saw d100 or d20. Because they make sense. Often the manufacturers don't know about this small anti-cheat measure, this is a fact. Also: that d8 is a very bad spin down, as consecutive numbers are not adjacent. For example, 4 is on the opposte side of 3. And 2 is not near 3 either, and 2 is on the opposite side of 1.

  • @Bluhbear

    @Bluhbear

    2 жыл бұрын

    When he's demonstrating in the video that the d8 doesn't have a consistent sum on opposite faces, he does so by showing that 5 is opposite 6, which means it can't be a spindown. (I've never even heard of a spindown d8.) Apparently, d8's are just made this way, with the important sums being the four faces surrounding a vertex, rather than opposite sides.

  • @naybala7884
    @naybala78842 жыл бұрын

    Finally new video out!!

  • @diegorodriguesdesouza7389
    @diegorodriguesdesouza73892 жыл бұрын

    Imagine having this guy as your GM

  • @jenshaglof8180
    @jenshaglof81802 жыл бұрын

    That took me a while to understand. Great trick!

  • @jktutorial007
    @jktutorial0072 жыл бұрын

    We cannot play this trick with others, coz you've huge fan base here in India 😊

  • @srinivasams9323

    @srinivasams9323

    2 жыл бұрын

    @@screenoholic especially on Delhi girls lol

  • @alainaedwards6053
    @alainaedwards60532 жыл бұрын

    In love with every Ben Sparks video because Ben Sparks

  • @PixelPhobiac
    @PixelPhobiac2 жыл бұрын

    This is sick! Can't wait to try it out

  • @milanchecc7649
    @milanchecc76492 жыл бұрын

    What an awesome and neat trick. Splendid. :D

  • @__Mr.Long__
    @__Mr.Long__2 жыл бұрын

    This is BRILLIANT

  • @lenny6281
    @lenny62812 жыл бұрын

    I actually understood this one pretty much instantly! Lots of free beer will be had!

  • @EmissaryOfSmeagol
    @EmissaryOfSmeagol2 жыл бұрын

    I'm proud to say that I actually figured out the trick before the reveal!

  • @matthewhubka6350
    @matthewhubka63502 жыл бұрын

    The thing in the top right keeping track of the dice made the trick easier to a lot figure out

  • @tedp9146
    @tedp91462 жыл бұрын

    This is gonna be fun in the next D&D session

  • @Sinebeast
    @Sinebeast2 жыл бұрын

    Happy to have figured it out on the second run :)

  • @pudicio
    @pudicio2 жыл бұрын

    Saw through this pretty quickly. He alsways has you add both sides of a die and knows all other info.

  • @n20games52
    @n20games522 жыл бұрын

    I can't wait to try it!

  • @rogerprat633
    @rogerprat6332 жыл бұрын

    gotta admit u got me on the first one! nice trick

  • @stevexl7747
    @stevexl77472 жыл бұрын

    Interesting as always, Ben!

  • @ShenghuiYang
    @ShenghuiYang2 жыл бұрын

    If you can do this in pub, that means you need more drinks.

  • @Tossen98
    @Tossen982 жыл бұрын

    Brilliant!

  • @mathgeek7966
    @mathgeek79664 ай бұрын

    Awesome! Ok, so I was compelled to pause the video and figure out why this works before you revealed the answer. Thanks to you for highlighting this fun Martin Gardner trick! 😊

  • @DJejbarros
    @DJejbarros2 жыл бұрын

    so simple... but so amazing

  • @annejohnson2398
    @annejohnson23982 жыл бұрын

    This is awesome! Can’t wait to try it at my next RPG session!

  • @angel-ig
    @angel-ig2 жыл бұрын

    Nice trick!

  • @tylernass6263
    @tylernass62632 жыл бұрын

    I'm much more impressed by how quickly they can both add the numbers up.

  • @GenericInternetter
    @GenericInternetter2 жыл бұрын

    Russell Crowe's tabletop-dice-trick videos are a really good follow-up to Gladiator and Master & Commander. Looking forward to the 2-hour cinematic version of these.

  • @TheThursty100
    @TheThursty1002 жыл бұрын

    It's quite fun if you think about it, because they can reroll as many dice as often as the want. You just need to know how often something got rerolled and the trick still works. You're just adding 7*n to the sum, since you take out the 7 every time you reroll

  • @Alex.R.L
    @Alex.R.L2 жыл бұрын

    I respect this guy's dice collection.

  • @effychase62
    @effychase622 жыл бұрын

    Great trick, love it

  • @Nothing2150
    @Nothing21502 жыл бұрын

    Amazing. I love it

  • @jeffhinchliffe
    @jeffhinchliffe2 жыл бұрын

    Martin Gardner was an absolute treasure! This version is a simplified handling. The original version of this routine involves turning over two dice and re-rolling them. This makes the procedure feel even more random and makes it a touch harder for the audience to deconstruct. Also, with re-rolling two of the dice, your range of possible totals is larger, allowing you to repeat with less of a chance for the same total to occur. Oh, and the original version of this routine was published in a book in France in 1584, so imagine someone was performing this at least a decade before the premiere of Romeo and Juliet!

  • @tjgrembowski

    @tjgrembowski

    2 жыл бұрын

    Thanks for the insight! Which book is this trick from? I saw he has lots of books, but I'd like to learn more like this.

  • @daselsdis653
    @daselsdis6532 жыл бұрын

    lets goooo, early to the new numberphile video, +7 gang

  • @rogerkearns8094
    @rogerkearns80942 жыл бұрын

    That's the best trick on KZread!

  • @rcb3921
    @rcb39212 жыл бұрын

    1:58 "Good" - ah yes, satisfied magician's face. I know you well.

  • @PrakashKumar-ls9ln
    @PrakashKumar-ls9ln2 жыл бұрын

    I paused the video and solved it successfully. Felt amazing 😂😂

  • @iteerrex8166
    @iteerrex81662 жыл бұрын

    Thats very simple yet very cool trick.

  • @thegodsea6003
    @thegodsea60032 жыл бұрын

    This was great!

  • @myownsite
    @myownsite2 жыл бұрын

    I pluralised die wrong *dies*

  • @expomath9348
    @expomath93482 жыл бұрын

    Toujours dans l'originalité et la bonne humeur ! Chaine extraordinaire pour nourrir la curiosité et la soif d'apprendre des plus jeunes et des plus agés 👍 For those who don't speak french, to translate in few word : Amazing content as usual , big up from France ! Signé /from: un modeste prof de math ( a modest math teacher )😘

  • @NetAndyCz

    @NetAndyCz

    2 жыл бұрын

    I do not speak French, but I can read it;) That is a very loose translation:)

  • @anon6514
    @anon65142 жыл бұрын

    btw: The dice are typically designed that way so they represent a variable in a table-top game. Because small change = small rotation. These variants are often called 'tick-down' dice. You do get d20 and d8 with the same property. Although, I'm surprised at the inconsistency with the bag you bought...

  • @EebstertheGreat

    @EebstertheGreat

    2 жыл бұрын

    Spindown D20s are used for MTG, but they aren't used that widely for tabletop games. (Some games use them, some don't, but most people use D20s designed for rolling anyway, which means opposite faces sum to 21.) They are used as counters much like a doubling cube in backgammon. The D8 here is also for rolling and has a different property: the sum of four faces meeting at any vertex is 18.

  • @vource2670
    @vource26702 жыл бұрын

    You talked tae my class on Monday, and will be doing it again emmrow

  • @0x19
    @0x192 жыл бұрын

    i was never surprised by it

  • @alphabeets
    @alphabeets2 жыл бұрын

    Great trick!

  • @mihancic
    @mihancic2 жыл бұрын

    Love this channel :)

  • @helloworld-ru9tz
    @helloworld-ru9tz2 жыл бұрын

    the real question is; if we could do it with 'n' number of dices. the general case would be much more amazing!

  • @bobrong9645

    @bobrong9645

    2 жыл бұрын

    Sum of all visible dices + 7*number of rerolls.

  • @Jeff-wn5sv

    @Jeff-wn5sv

    2 жыл бұрын

    As long as the dice used all share the same number of faces, and opposite faces sum in a predictable manner.

  • @taragnor

    @taragnor

    2 жыл бұрын

    I mean you can add up as many dice + opposite sides as you want and reroll. It's just that the more you do it, the more obvious to the other person how the trick works since they'll all add up to 7. And once you know that, the trick is really simple how it works.

  • @Rohit-xp9fy
    @Rohit-xp9fy2 жыл бұрын

    I got the trick before his explanation but I enjoyed the video 😄

  • @mythicgamer6291
    @mythicgamer6291 Жыл бұрын

    Great video

  • @KeithKeydel
    @KeithKeydel2 жыл бұрын

    Cool trick, I'll try this with my kids and see how long until they figure it out.

  • @lonestarr1490

    @lonestarr1490

    2 жыл бұрын

    I'd say it depends on if they already know that opposite sides of a dice always add up to 7.

  • @jtorola

    @jtorola

    2 жыл бұрын

    I’m planning on blowing some of my nieces and nephews minds tonight

  • @SarthakShah-cb1ii

    @SarthakShah-cb1ii

    2 жыл бұрын

    Let me tell you being a kid from this generation….they definitely will

  • @bacondoesthings123
    @bacondoesthings1232 жыл бұрын

    Martin Gardener is an absolute legend.

  • @JonathanTot
    @JonathanTot2 жыл бұрын

    i love the slow infiltration of D&D into Numberphile ... Before long we'll have a live play series: Discriminants & Divisors

  • @TheAwes0meo
    @TheAwes0meo2 жыл бұрын

    Saw through this trick instantly. Still plan on using it though!

  • @electricwizard5747

    @electricwizard5747

    2 жыл бұрын

    yeah right

  • @Benja.____
    @Benja.____2 жыл бұрын

    This is so cool!!

  • @skakdosmer
    @skakdosmer2 жыл бұрын

    Very nice trick.

  • @luketurner314
    @luketurner3142 жыл бұрын

    You could turn it up a notch by asking if they would like to repeat the 2nd and 3rd steps (add opposite side and re-roll). You would just keep adding 7 each time. This would give the illusion that they're making choices. However, it may also allow them to figure it out sooner.

  • @viddev1442
    @viddev14422 жыл бұрын

    I'm impressed by that he could do the math so quick while talking

  • @Luca_5425
    @Luca_54252 жыл бұрын

    Cool trick

  • @CoreTorque
    @CoreTorque Жыл бұрын

    @Numberphile watching your video it occurred to me that you could have them "repeat the stage where you add the bottom of the dice and roll it again" many times, just add +7 for every re-roll. However at the pub it may become increasingly difficult to count how many re-rolls!

  • @wearebarbiefans
    @wearebarbiefans2 жыл бұрын

    He's back yaaaayyy

  • @sonaruo
    @sonaruo2 жыл бұрын

    When person see the 3 dice its missing the 7 you make with 1 of them in previous steps

  • @scottjacoby2594
    @scottjacoby25942 жыл бұрын

    Pausing at 3:46 to say, it’s because you’re eliminating the significance of the original result of the rerolled die by adding the bottom to make 7. So of course the answer is going to be the new result of the rerolled die + the two results of the other dice + 7 = the total sum Edited for typos

  • @Markus_Aleksandr
    @Markus_Aleksandr2 жыл бұрын

    There are also D20s that do not have this property, as they are predominantly used in Magic: The Gathering and other like-games for counting health totals (and so go from 20 to 1 in sequence across the faces).

  • @ragnkja

    @ragnkja

    2 жыл бұрын

    They’re not typically rolled, though, are they?

  • @portobellomushroom5764

    @portobellomushroom5764

    2 жыл бұрын

    @@ragnkja not usually, but if they're shaken well they're theoretically just as fair as an opposite-sum-21 die

  • @rmsgrey

    @rmsgrey

    2 жыл бұрын

    For M:tG, you can use a spindown d20 to randomise who picks who plays first. I prefer to do "odd or even" for the simulated coin flip rather than "high or low" because all the high numbers are on one hemisphere, with all the low numbers on the other.

  • @cygil1

    @cygil1

    2 жыл бұрын

    I accidentally bought one of these the other day. I was wondering what it was for.

  • @anaycoding6594
    @anaycoding65942 жыл бұрын

    "I'm impressed that you are impressed" best quote ever

  • @callmekenneth8133
    @callmekenneth81332 жыл бұрын

    Love it. Brilliant and simple. Just like true magic 🕋

  • @rs0wner301

    @rs0wner301

    2 жыл бұрын

    Alhamdulilah

  • @nimrod9
    @nimrod92 жыл бұрын

    I'm proud that I got it before it was explained. Yay!

  • @dfmayes
    @dfmayes2 жыл бұрын

    This is the first Numberphile video I figured out before the explanation. Yay me!

  • @mythicgamer6291
    @mythicgamer62912 жыл бұрын

    great video

  • @bersbatjargal2074
    @bersbatjargal20742 жыл бұрын

    Insane

  • @jeffreyjefferson536
    @jeffreyjefferson5362 жыл бұрын

    Oooh that's a neat trick! I'm gonna try it on everybody I know ASAP :D And I got it before the explanation - yay :]

  • @jonkirk2118
    @jonkirk21182 жыл бұрын

    Great stuff. To really misdirect people, the person doing the trick should, after working out the number, reroll the dice, then pretend to think for a moment, and then call out the number.

  • @estefencosta1835
    @estefencosta18352 жыл бұрын

    Very cool.

  • @ThePCguy17
    @ThePCguy172 жыл бұрын

    The reason why a lot of dice might not have the same sum for every set of opposite sides is that when a die is made for the purpose of random number generation it's more common to make sure that similar numbers are never next to each other. So, for example, 1 will usually be next to the highest or second highest number, while two will be on or near the opposite side. This means that even a talented throw will have much more difficulty landing the die on a certain desired roll. Alternatively, some players just roll hard enough that it's clear they aren't picking and choosing their results. Still, it's nice not to have to worry about stuff like that.

  • @aameen951
    @aameen9512 жыл бұрын

    It's amazing when you realize that the first two dice don't even matter

  • @fv9422

    @fv9422

    2 жыл бұрын

    It is so painfull when you see it straight away but the video is still 6 minutes long...

  • @cr10001
    @cr100012 жыл бұрын

    Yeah I could see it after the first couple of rolls. You pick a dice, add on the 'bottom' of it - so that's 7 - then you re-roll it. So the 3 dice now showing are the two unaltered ones, plus whatever is now showing on the re-rolled dice; and the total in your mind is the two unaltered ones plus 7 plus whatever is now showing on the re-rolled dice. Simple yet cunning!

  • @ClickClack_Bam
    @ClickClack_Bam2 жыл бұрын

    There are dice which are used for scoring so there's ease to find the next number down or up. Then there's random dice used to roll for a random number.

  • @hierismail
    @hierismail2 жыл бұрын

    Oooohhh, I am so proud of myself. I think I got it after the second example in the introduction. You don't know which number was picked, turned around and changed. However: the sum of 2 opposite sides of a d6 is always 7. So whatever is the end result of the dice, add 7 and you have the answer.

  • @stephenkamenar
    @stephenkamenar2 жыл бұрын

    i knew the 7 thing, most people do, but it was still surprising. because you could choose which to reroll. took me a minute to realize the 7 thing was all that mattered

  • @danielrhouck
    @danielrhouck2 жыл бұрын

    Icosahedral dice are also made in different versions. Some are “spin-down”, where consecutive numbers are adjacent. Useful for Magic: the Gathering life trackers; not so much for fair rolls or this trick.

  • @thekingofcheese9005
    @thekingofcheese90052 жыл бұрын

    The problem with trying this trick on people is way too many people will fail to follow the instructions correctly and end up with the wrong mental number, which will make the prediction seem 'wrong'.

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