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Three Dice Trick - Numberphile 

Numberphile
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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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22 авг 2024

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Комментарии : 493   
@martinfladby6158
@martinfladby6158 3 года назад
I like that this video is 7 minutes long
@wobblysauce
@wobblysauce 3 года назад
magic.
@brumd
@brumd 3 года назад
That definitely means it has been edited down from 14 minutes.
@abnatian
@abnatian 3 года назад
Long(er) than expected I'd say, regarding the usual audience.
@Triantalex
@Triantalex 8 месяцев назад
??
@AldrichNaiborhu
@AldrichNaiborhu 3 года назад
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 3 года назад
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 3 года назад
@@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 3 года назад
@@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 3 года назад
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 8 месяцев назад
??
@SeanHodgins
@SeanHodgins 3 года назад
All tricks are usually simple, its obfuscating the simplicity that makes it cool. This one is very cool.
@iwersonsch5131
@iwersonsch5131 3 года назад
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 3 года назад
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 3 года назад
@@Vlow52 or you're over thinking their comment a little
@BinaryBolias
@BinaryBolias 3 года назад
Less obfuscated if you use a radix seven numeral system.
@seshamohansrivatsavamaddal1160
@seshamohansrivatsavamaddal1160 3 года назад
Obfuscating.... Hmmmm
@fast-eddie-clarke
@fast-eddie-clarke 3 года назад
thanks for all the free beer I'm gonna get at the pub now
@reidflemingworldstoughestm1394
@reidflemingworldstoughestm1394 3 года назад
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 3 года назад
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 8 месяцев назад
??
@capfer77018
@capfer77018 3 года назад
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 3 года назад
The d8 shown in this video can’t be a spin down dice because consecutive numbers are on opposite faces
@joaopaulomendonca1414
@joaopaulomendonca1414 3 года назад
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 3 года назад
But it is well balanced in the sense that each set of four numbers that share a vertex sum up to 18
@yuvalne
@yuvalne 3 года назад
+
@X_Baron
@X_Baron 3 года назад
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.Rodriguez 3 года назад
This may be the first time I got the trick before the explanation. And now I'm so happy :)
@Eggnog18
@Eggnog18 3 года назад
You and me both! I feel so smart, even though I blank at most of the other videos. lol
@wayoutdan8334
@wayoutdan8334 3 года назад
same here
@Triantalex
@Triantalex 8 месяцев назад
??
@sephalon1
@sephalon1 3 года назад
The top and bottom of a 6-sided-die always total to 7. There. That's like 95% of dice tricks.
@dermaniac5205
@dermaniac5205 3 года назад
And most of us learn that as children
@scottllewellyn8221
@scottllewellyn8221 3 года назад
yeah I was gonna say surely it's not that hard... I figured it out straight away
@cybersoul3371
@cybersoul3371 3 года назад
@@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 3 года назад
@@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 3 года назад
I knew that but I still did not get it until it was explained.
@RedStinger_0
@RedStinger_0 3 года назад
Brady's gasp was precious.
@gx_no
@gx_no 3 года назад
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 3 года назад
As soon as he said at 0:07 that he had a blindfold, I knew what the trick was going to be.
@jacobkaneff8261
@jacobkaneff8261 3 года назад
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 3 года назад
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 3 года назад
@@viliml2763 As soon as I saw the video title I knew what the truck was going to be
@hyfy-tr2jy
@hyfy-tr2jy 3 года назад
Always love new videos from the resident "Maximus the Mathematician". You have to admit he looks like Russell Crowe
@WetBanditYGO
@WetBanditYGO 3 года назад
Lol I was just thinking that!
@Triantalex
@Triantalex 8 месяцев назад
false.
@jansenart0
@jansenart0 3 года назад
OR, a simpler explanation, is that he's a WARLOCK
@feraldreams7978
@feraldreams7978 3 года назад
Dungeon Keeper intensifies!!
@illusionist1872
@illusionist1872 3 года назад
His patron is Michael Stevens
@jansenart0
@jansenart0 3 года назад
@@illusionist1872 A suspiciously normal name.
@illusionist1872
@illusionist1872 3 года назад
@@jansenart0 Vsauce. I was referring to Vsauce.
@marc0s158
@marc0s158 3 года назад
Only mathematics and TTRPG players have those dice. Im thinking he is both
@livedandletdie
@livedandletdie 3 года назад
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.
@ShenghuiYang
@ShenghuiYang 3 года назад
If you can do this in pub, that means you need more drinks.
@HonkeyKongLive
@HonkeyKongLive 3 года назад
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 2 года назад
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.
@raedev
@raedev 3 года назад
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
@rcb3921
@rcb3921 3 года назад
1:58 "Good" - ah yes, satisfied magician's face. I know you well.
@snatchngrab8262
@snatchngrab8262 3 года назад
It's the "do you remember what happened in the middle" part that is the actual magic.
@diegorodriguesdesouza7389
@diegorodriguesdesouza7389 3 года назад
Imagine having this guy as your GM
@jktutorial007
@jktutorial007 3 года назад
We cannot play this trick with others, coz you've huge fan base here in India 😊
@srinivasams9323
@srinivasams9323 3 года назад
@@screenoholic especially on Delhi girls lol
@GenericInternetter
@GenericInternetter 3 года назад
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.
@jeffhinchliffe
@jeffhinchliffe 3 года назад
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 3 года назад
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.
@camdix3250
@camdix3250 Год назад
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.
@AMorphicTool
@AMorphicTool 3 года назад
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.
@FogToo
@FogToo 3 года назад
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 3 года назад
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 3 года назад
@@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 3 года назад
@@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 3 года назад
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.
@EmissaryOfSmeagol
@EmissaryOfSmeagol 3 года назад
I'm proud to say that I actually figured out the trick before the reveal!
@daselsdis653
@daselsdis653 3 года назад
lets goooo, early to the new numberphile video, +7 gang
@expomath9348
@expomath9348 3 года назад
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 3 года назад
I do not speak French, but I can read it;) That is a very loose translation:)
@vonriel1822
@vonriel1822 3 года назад
Who cares about the trick, Ben Sparks plays D&D. I kinda wanna see an all-Numberphile-guest game now.
@Matthew-bu7fg
@Matthew-bu7fg 3 года назад
i'll be using this one on my students. Great video!
@KeithKeydel
@KeithKeydel 3 года назад
Cool trick, I'll try this with my kids and see how long until they figure it out.
@lonestarr1490
@lonestarr1490 3 года назад
I'd say it depends on if they already know that opposite sides of a dice always add up to 7.
@jtorola
@jtorola 3 года назад
I’m planning on blowing some of my nieces and nephews minds tonight
@SarthakShah-cb1ii
@SarthakShah-cb1ii 3 года назад
Let me tell you being a kid from this generation….they definitely will
@pudicio
@pudicio 3 года назад
Saw through this pretty quickly. He alsways has you add both sides of a die and knows all other info.
@tedp9146
@tedp9146 3 года назад
This is gonna be fun in the next D&D session
@oafkad
@oafkad 3 года назад
This is so cool. I can't get over how much I like it.
@JonathanTot
@JonathanTot 3 года назад
i love the slow infiltration of D&D into Numberphile ... Before long we'll have a live play series: Discriminants & Divisors
@CoreTorque
@CoreTorque 2 года назад
@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!
@lenny6281
@lenny6281 3 года назад
I actually understood this one pretty much instantly! Lots of free beer will be had!
@helloworld-ru9tz
@helloworld-ru9tz 3 года назад
the real question is; if we could do it with 'n' number of dices. the general case would be much more amazing!
@bobrong9645
@bobrong9645 3 года назад
Sum of all visible dices + 7*number of rerolls.
@Jeff-wn5sv
@Jeff-wn5sv 3 года назад
As long as the dice used all share the same number of faces, and opposite faces sum in a predictable manner.
@taragnor
@taragnor 3 года назад
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.
@Markus_Aleksandr
@Markus_Aleksandr 3 года назад
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 3 года назад
They’re not typically rolled, though, are they?
@portobellomushroom5764
@portobellomushroom5764 3 года назад
@@ragnkja not usually, but if they're shaken well they're theoretically just as fair as an opposite-sum-21 die
@rmsgrey
@rmsgrey 3 года назад
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 3 года назад
I accidentally bought one of these the other day. I was wondering what it was for.
@matthewhubka6350
@matthewhubka6350 3 года назад
The thing in the top right keeping track of the dice made the trick easier to a lot figure out
@thekingofcheese9005
@thekingofcheese9005 3 года назад
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'.
@jonkirk2118
@jonkirk2118 2 года назад
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.
@tylernass6263
@tylernass6263 3 года назад
I'm much more impressed by how quickly they can both add the numbers up.
@anon6514
@anon6514 3 года назад
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 3 года назад
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.
@anaycoding6594
@anaycoding6594 2 года назад
"I'm impressed that you are impressed" best quote ever
@unclecreepy4185
@unclecreepy4185 3 года назад
I don’t know what this video is about, but it better help me win D&D.
@aameen951
@aameen951 3 года назад
It's amazing when you realize that the first two dice don't even matter
@fv9422
@fv9422 3 года назад
It is so painfull when you see it straight away but the video is still 6 minutes long...
@bacondoesthings123
@bacondoesthings123 3 года назад
Martin Gardener is an absolute legend.
@myownsite
@myownsite 3 года назад
I pluralised die wrong *dies*
@elfrancescaino2465
@elfrancescaino2465 3 года назад
Is it possible to do a similar trick with different dice? I think not because you wouldn't know what to add to the final top faces but maybe I just didn't figure it out
@rmsgrey
@rmsgrey 3 года назад
You could do it if you flip and reroll all the dice, but you couldn't do it if you don't know what size dice have been rerolled.
@TheThursty100
@TheThursty100 3 года назад
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
@KarlHamilton
@KarlHamilton 3 года назад
Brilliant, cheers for this :)
@jenshaglof8180
@jenshaglof8180 3 года назад
That took me a while to understand. Great trick!
@sonaruo
@sonaruo 3 года назад
When person see the 3 dice its missing the 7 you make with 1 of them in previous steps
@emmettchan5545
@emmettchan5545 3 года назад
Am I the only one that immediately recognized that you just add the 7 that is always added to the current total?
@luketurner314
@luketurner314 3 года назад
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.
@scottjacoby2594
@scottjacoby2594 3 года назад
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
@sanketmanna8653
@sanketmanna8653 3 года назад
At 3:00, I'm like "Ohhhh!! That's one of the coolest trick ever."
@alvinhelms2170
@alvinhelms2170 7 месяцев назад
It is surprisingly gratifying that I instantly understood the trick when I saw it, without yet hearing the explanation. It probably doesn't really merit much pride, but perhaps a tiny ego boost is forgivable.
@dragoda
@dragoda 3 года назад
As usual, this channel is amazing.
@althermella8633
@althermella8633 3 года назад
I saw it the first time so I don't think it will work reliably if I'd try to do it
@dfmayes
@dfmayes 3 года назад
This is the first Numberphile video I figured out before the explanation. Yay me!
@planchetflaw
@planchetflaw 3 года назад
Sum of free beers earned from this channel = 12
@vource2670
@vource2670 2 года назад
You talked tae my class on Monday, and will be doing it again emmrow
@unclecreepy4185
@unclecreepy4185 3 года назад
A great trick to impress 2nd graders and anyone else who has never seen a 6-sided die.
@unclecreepy4185
@unclecreepy4185 3 года назад
Pick any 3 numbers. Now add 7 to it and think of that number, but don’t let me know what it is. Now show me the 3 numbers you picked and I’ll magically tell you the number you’re thinking of. Think of the year you were born. Now add your age to that number. Now, if you haven’t had your birthday yet, add 1 to that number, if you had your birthday, add 0. Think about the new number without telling me. Now, without me knowing if you’d had a birthday or not, I will magically guess the number you’re thinking of. Pick any number between 1 and 100. Write that number down. Subtract 100 from that number and think about that number, don’t tell me. Now show me what you wrote down and I’ll magically guess the new number you’re thinking about.
@stephenkamenar
@stephenkamenar 3 года назад
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
@naybala7884
@naybala7884 3 года назад
Finally new video out!!
@Sinebeast
@Sinebeast 3 года назад
Happy to have figured it out on the second run :)
@alainaedwards6053
@alainaedwards6053 3 года назад
In love with every Ben Sparks video because Ben Sparks
@vsm1456
@vsm1456 3 года назад
I love videos with Ben! Please do more. :D
@LinkHeroOfHy
@LinkHeroOfHy 3 года назад
typically, for any die where the number of sides are even, the sum of opposite sides is d+1, where d = number of sides (excepting that pesky d8). this is generally the case, when the die manufacturer uses the flip-turn method of assigning die faces, that is starting from 1, you flip the die over and turn one face in the left or right direction, until you reach face number d. these are considered "fair" dice, as the distribution of high and low numbers is scattered across all faces, rather than clumped around a common vertex for lows, and opposite for highs this will hold true on most dice all the way from a d2 (essentially a coin where heads/tails is replaced by 1/2) all the way to mathsgear's d120 (don't recall if they've developed a d240 or not)
@PrakashKumar-ls9ln
@PrakashKumar-ls9ln 2 года назад
I paused the video and solved it successfully. Felt amazing 😂😂
@divyanshusrivastava5028
@divyanshusrivastava5028 3 года назад
This trick is so simple but still a little complicated to throw someone off.
@mathgeek7966
@mathgeek7966 7 месяцев назад
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! 😊
@rogerprat633
@rogerprat633 3 года назад
gotta admit u got me on the first one! nice trick
@FirstLast-gw5mg
@FirstLast-gw5mg 3 года назад
Easy if you know that the numbers on opposite faces add up to 7. So you're turning the first value of the dice that you re-roll into a 7 and the result is just the sum of the 3 dice at the end plus 7.
@rgbtryhardled636
@rgbtryhardled636 3 года назад
Anyone else feel like tricks on RU-vid are getting simpler and simpler. This one was pretty obvious. Still love numberphile.
@WhyWorldSucks
@WhyWorldSucks 3 года назад
Here before he explains it. I figured it out. YES.
@chandir7752
@chandir7752 2 года назад
the sum of the opposite faces of any evenly distributed die is the biggest number on the die +1. I mean it's not hard to pick two random opposite faces and add them up, but this is nice and easy and elegant, it's similar to Gauß's idea with the 1+20, 2+19, 3+18, ...
@0x19
@0x19 3 года назад
i was never surprised by it
@solalabell9674
@solalabell9674 2 года назад
The only opposite side sun for things such as a d12 or d20 is always the number of faces + 1
@__Mr.Long__
@__Mr.Long__ 3 года назад
This is BRILLIANT
@angel-ig
@angel-ig 3 года назад
Nice trick!
@ThePCguy17
@ThePCguy17 3 года назад
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.
@SnoopyDoofie
@SnoopyDoofie 3 года назад
Since when did Russell Crowe become a mathematician?
@testname547
@testname547 3 года назад
When he played in the movie, "A Beautiful Mind" 2001 :D
@yabannamba7678
@yabannamba7678 3 года назад
@@testname547 trueeee
@Alex.R.L
@Alex.R.L 3 года назад
I respect this guy's dice collection.
@Lala-yz9mu
@Lala-yz9mu 3 года назад
OMG I FINALLY GOT ONE BEFORE THE EXPLANATION! I've peaked, all is well now.
@hierismail
@hierismail 3 года назад
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.
@BritishBeachcomber
@BritishBeachcomber 7 месяцев назад
Martin Gardner's articles in Scientific American were essential reading for the 10 year old me.
@wearebarbiefans
@wearebarbiefans 3 года назад
He's back yaaaayyy
@rickintexas1584
@rickintexas1584 3 года назад
I’m a professional magician. And I know about the 7s. And I have a MS in Mechanical Engineering. But this truck still fooled me. I will use this!
@cr10001
@cr10001 3 года назад
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!
@nimrod9
@nimrod9 3 года назад
I'm proud that I got it before it was explained. Yay!
@Luca_5425
@Luca_5425 3 года назад
Cool trick
@sofiasarigiannidi8708
@sofiasarigiannidi8708 3 года назад
I don't want to sound cocky but this was a bit too obvious for me. But I am glad to see so many people in the comments who were surprised and enjoyed it.
@JamieDNGN
@JamieDNGN 3 года назад
the d8s made by a Polish dice producer - Q Workshop - are designed so that they follow the rule of opposite sides
@peacockmoss1491
@peacockmoss1491 3 года назад
The way this is going, I wouldn't be suprised if Brian Brushwood will be a guest after Covid lifts up
@Volti21
@Volti21 3 года назад
Yes. For those who does not want to watch it all, even it is only 7 minutes. Tell the guy what to do, when he does it, open your eyes, sumarize what you see and add 7.
@viddev1442
@viddev1442 3 года назад
I'm impressed by that he could do the math so quick while talking
@BillM1960
@BillM1960 3 года назад
I knew it had something to do with 7 but didn't get it until you explained it.
@Bloberis
@Bloberis 3 года назад
I once knew a guy who had a few sets of dice where opposite faces were not determined by the number, but by the weight of material removed to carve that number in as they were trying to make the most balanced die possible. The chaotic numbering made me irrationally upset to look at, I'll take my unbalanced and numerically pleasing dice every time
@patu8010
@patu8010 3 года назад
At that point why not just paint the numbers on or something
@jursamaj
@jursamaj 3 года назад
Wouldn't be hard to just cut the numbers to depths inverse to area. Or do like Vegas dice, filling the grooves with a similar density material. Clearly, more balanced than the method you describe is possible, so they failed.
@Bloberis
@Bloberis 3 года назад
@@patu8010 even paint has mass
@Bloberis
@Bloberis 3 года назад
@@jursamaj I feel like if you carved all the numbers to different depths you'd end up with a really ugly die
@jursamaj
@jursamaj 3 года назад
@@Bloberis I don't see why, but that was only 1 solution.
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