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        riddles >> easy >> Three Dots
        
(Message started by: The_Godfather on Mar 29^th, 2005, 8:28am)

Title: Three Dots
Post by The_Godfather on Mar 29^th, 2005, 8:28am

Okay, now this riddle is supposed to be easy, but I can't figure it out!

You are wandering an unknown forest when you are captured by tiny forest people. They keep calling you, "A smart person." When you get to their camp, they sit you down with two other people and tell you that you will be competing to take over as the cheif of the forest people.

You are put in an equillateral triangle where each person can see the other two people. The cheif then blindfolds the three of you and says, "I am going to put a green or red dot on each of your foreheads, and when I unblindfold you, if you see a green dot, raise your hand.

The cheif puts a green dot on all three foreheads and takes off your blindfolds. He says, "If you know what color dot you have, tell me and tell me why. The smartest person, you, says, "I have a green dot. The reason I know this is....."

I can't figure this out! Any help would be appreciated.

Title: Re: Supposed to be easy, but I can't figure it out
Post by Phade on Mar 29^th, 2005, 9:02am

This guy can see both other people's dots are red, and they are both raising their hands.

Title: Re: Supposed to be easy, but I can't figure it out
Post by Phade on Mar 29^th, 2005, 9:21am

Whoa, sorry, I read that wrong. I'll get back to you

Title: Re: Supposed to be easy, but I can't figure it out
Post by towr on Mar 29^th, 2005, 9:23am

If you had a red dot and the other two had a green dot; consider what either of them could figure out when everyone raises their hands.

Title: Re: Three Dots
Post by Icarus on Mar 29^th, 2005, 4:50pm

Godfather, you have put in your support on some of William's other instructions, but you seem to have missed this one: "Please use meaningful titles".

It is helpful when reviewing the threads to have something that reminds you of the content of each thread before you open it. If we let people get away with it, half the threads in here would be named something like "HELP!" or "I can't solve this".

Title: Re: Three Dots
Post by Speaker on Mar 29^th, 2005, 11:02pm

Is it impossible to tell what color dot you have? It seems to be impossible to me. But, then these riddles usually do seem impossible.

The two people in front of you have green dots.
All three people raise their hands.
This would happen whether you have a green dot or a red dot. So, there is no certainty. (is there?)

Okay, now I get it. The old I knew what you knew before you knew what I knew ploy.

But, I think a better answer would be: "Well chief, you have only green paint on your finger, so you must have put green on everyone."

Title: Re: Three Dots
Post by Icarus on Mar 30^th, 2005, 2:52pm

To explain the solution: Suppose you had a red dot. Then the other two, upon seeing everyone raise their hands, would know immediately that they have green dots (for if you have a red dot, each would know that the only green dot the third guy could see would be the one on his forehead). Since neither immediately announces his color, you realize that they must not be able to make this deduction, and so it must be that you also have a green dot.

Now: let me give you this variant:

The chief (who has now learned how to spell his own title ;)) wants to select the most intelligent successor he can. He finds three likely candidates, and lets them know that he wants to find the most intelligent by a fair contest. He will blindfold each, then paint a red or green dot on each forehead. When he announces he is done, everyone is to remove their blindfolds, and raise their hands if they see a green dot. The first person to tell the color of their own dot, and give valid reasoning behind their choice, will be declared the winner.

(Note that in this version we are not told that the chief colors everyone green).

As the chief approaches one of the men to blindfold him, the man announces the color the chief will give him, and why. The chief declares that the man is correct and is the new successor.

What color did the man announce, and how did he know it before it was even painted on?

Title: Re: Three Dots
Post by The_Godfather on Mar 30^th, 2005, 4:51pm

But, I think a better answer would be: "Well chief, you have only green paint on your finger, so you must have put green on everyone."

Speaker: if the answer was that simple, it wouldn't be a riddle. Don't post obviously irrelevant answers, please. Thanks for your opinion, but please state your reasoning and make sure you have some. :P

Title: Re: Three Dots
Post by SWF on Mar 30^th, 2005, 5:53pm

Isn't there some assumption as to how long it would take the others to have figured out their color?

If you like this riddle, there are several others here that are similar. For example, 1 (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_medium;action=display;num=1042192723) 2 (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_hard;action=display;num=1054592392) 3 (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_medium;action=display;num=1032293102) 4 (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_hard;action=display;num=1028010706) 5 (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_medium;action=display;num=1047087194)

Title: Re: Three Dots
Post by Speaker on Mar 30^th, 2005, 7:10pm

Thanks for the advice Godfather. I will endeavor to limit my alternative answers to those that more closely approach equivalence to that answer which the riddler has in mind.

Wait a minute, that means I would not be able to post humorous answers, or wild guesses. So, regardless of preceding statements, I refuse to take your advice. I will continue, in the spirit of "no answer is stupid" (a corrallary to "no question is stupid") to answer with any answer that I, and I alone, feel has merit, including but not limited to any tangential reference to just about anything on God's green earth and adjacent environs.

Title: Re: Three Dots
Post by The_Godfather on Mar 30^th, 2005, 7:19pm

WOW, speaker. You must be incredibly high. I now respect you >:(

Title: Re: Three Dots
Post by The_Godfather on Mar 30^th, 2005, 7:39pm

These are all good answers (except the aforementioned) and I think there are more. Anyone's consent logically, mathematically, ect. Please, no crap intended to be funny just so you can laugh all by yourself.

Title: Re: Three Dots
Post by TheGodfather234 on Mar 30^th, 2005, 7:52pm

darnit grant you know thats all i'm good at!!!!!!! :( >:( :'( :'( :'( :'( :-/sorry im rilly high now... like speaker!!! ;D

Title: Re: Three Dots
Post by TheGodfather234 on Mar 30^th, 2005, 7:56pm

Note to self: don't sniff markers...

Title: Re: Three Dots
Post by Grimbal on Mar 30^th, 2005, 11:59pm

The contest is supposed to be fair. It wouldn't be if the contestants didn''t all have the same color. Seeing that the other 2 have a green dot, it is quite obvious that you also have a green dot.

Title: Re: Three Dots
Post by The_Godfather on Mar 31^st, 2005, 8:28am

Thanks, Grimbol, but that answer has already been posted. Keep in touch! ;D

Title: Re: Three Dots
Post by Grimbal on Mar 31^st, 2005, 2:05pm

Yeah, The_Godfother, I am just trying to find new variations to an old problem.

I'll try to pass by and have a look from time to time...

Title: Re: Three Dots
Post by The_Godfather on Mar 31^st, 2005, 2:14pm

on 03/31/05 at 14:05:02, Grimbal wrote:

I'll try to pass by and have a look from time to time...

;)

Title: Re: Three Dots
Post by Icarus on Mar 31^st, 2005, 6:53pm

on 03/30/05 at 23:59:27, Grimbal wrote:

The contest is supposed to be fair. It wouldn't be if the contestants didn''t all have the same color. Seeing that the other 2 have a green dot, it is quite obvious that you also have a green dot.

Sorry, but in my variation, the chief has not even gotten out his paints yet, much less placed dots of any color on the other two.

on 03/30/05 at 16:51:49, The_Godfather wrote:

Speaker: if the answer was that simple, it wouldn't be a riddle. Don't post obviously irrelevant answers, please. Thanks for your opinion, but please state your reasoning and make sure you have some. :P

If there is one thing that I will not tolerate, it is someone with an overinflated sense of their own worth who tries to prop up their ego by being insulting to others. Some of your posts here and elsewhere seem to push this boundary strongly, or cross it. Please keep your ego in check, and let others have their say, even if you do not like it.

Title: Re: Three Dots
Post by TheGodfather234 on Mar 31^st, 2005, 7:52pm

Anything Grant or I have said was merely a comment not meant to offend or hurt anyone's feelings. As we are merely trying to get a point across that these are riddles, not simple concrete answers, we mean no damage. If you think that this is not a good thing to do merely don't do it. We do not do this for an ego trip or to feel above others, yet merely to express our opinions or that the answers are not one thougt lines. If we offended you then we did not mean to.

Title: Re: Three Dots
Post by Icarus on Mar 31^st, 2005, 9:47pm

Reading some of the other threads, I understand now. The problem is that you are young (though there are many others who are as young who participate in this thread, and a rare few who are younger). Therefore you really don't follow a lot of what is going on in our conversations. (I'm sorry that sounds insulting. It is not my intent to demean. It is simply a fact of life that at 12 and 13 you do not have the experience, the mindset, to understand why we say some of the stuff that we do. This is not something that you magically get at a certain age, either. As time goes by I still regularly discover that something I was sure I understood before has layers and meanings I had never noticed.)

You two are fixated on getting a specific answer, and react badly when someone does not provide it. But there are many aspects of any riddle, and we like to view things from other directions. Indeed, what you take as less than serious solutions, are in fact quite serious. Part of the problem is that you see only one answer, where as we see many that all work equally well. There is a thread somewhere around here on "Kindergarten Math" about a question that kindergartners are far more likely to answer correctly than college students. It is not that the kindergartners know something the college students do not. Rather the problem is, the college students have tools available that they turn to for this sort of problem that the kindergartners do not. But in this case, the standard tools are not what is needed. Since the kindergartners do not know them, they do not waste their time on them. Instead, they look at something else - which is exactly what the problem wants. So what is obvious to you may not be obvious to someone older who knows other possibilities.

Also, just because someone views your thread and doesn't post does not mean that they do not know the answer. I seldom answer riddles in the easy forum whether I know the answer or not. The only reason I made an exception for this one is that your original riddle has been posted and answered many times before. And I wanted to offer the variation, which is harder (though still easy in my estimation). Even easy puzzles usually wait a while before someone posts an answer. Other posters wait days and weeks before despairing that anyone will answer the question.

Title: Re: Three Dots
Post by The_Godfather on Apr 1^st, 2005, 6:55am

Just to add on to what TheGodfather234 said, when I seem rude or egotistic, all I want is to get them into the argument mode.

When you feel someone as insulted your opinion or way of thinking, you almost always feel you must defend yourself.

The object is not to hurt, simply to create debate. If everyone has an opinion, what better way to show it than a debate? Apparently, the mods have misunderstood my reasoning.

:(

Title: Re: Three Dots
Post by towr on Apr 1^st, 2005, 12:34pm

There is a difference between bickering, arguing, debating and discussing..
I prefer the latter myself, it allows you to explore a problem more fully, since you don't get stuck in the trenches..

Title: Re: Three Dots
Post by Speaker on Apr 4^th, 2005, 12:34am

Here is an attempt at Icarus's variation.

Assuming that the tribe believes that you are a very intelligent person (more intelligent than the other two candidates). Then, the test is to assess your abilities, not a test of who of the three is smartest.
So, in order to get you to use the method of "I know something because I know that you do not know it." Which is the method required to answer the first question. And, therefor it is the method the chief wants you to demonstrate to prove your intelligence. Then, you could assume (determine) that the chief would paint a dot on your head that is a different color from the other two dots. So, you could say to the chief.
"You will put a dot that is different from both of the other people on my head."

I do not know if this will hold up under scrutiny, but there you go.

Title: Re: Three Dots
Post by Avo on Apr 4^th, 2005, 8:07am

on 04/01/05 at 12:34:58, towr wrote:

There is a difference between bickering, arguing, debating and discussing..

It seems to me that towr and many others have blamed two people for one's mistakes. TheGodfather234 has been, and deserved to be, blamed for many actions. However, The Godfather merely acted in defense to yours and other mod's misdirected complaints toward him. I believe it is not him, but you to blame for his taking leave. You chased him away. I am a tad sickened by your obvious self-involvement. :'(

Title: Re: Three Dots
Post by towr on Apr 4^th, 2005, 8:42am

Well, since you've revealed elsewhere that you're The_Godfather.
I'd just say it's not fair to pin it all on the other one.

But let's just put it behind us.

Title: Re: Three Dots
Post by rmsgrey on Apr 4^th, 2005, 9:54am

on 04/04/05 at 08:07:21, Avo wrote:

I admit that I am sufficiently mentally lazy not to keep direct track of the precise name of all posters to this site, or which identity goes with which name. Add to that the fact that the two of you obviously know each other in your real life identities, and I end up lumping the pair of you together - at least in my early assessments. Having seen a couple of hundred posts between you, I'm beginning to get a feel for which of you is which, but I still think of you as a single category with two members rather than entirely separate entities.

As far as giving "silly" answers goes, there are four reasons why I do so:
1) I am unable to figure out what the question is asking for, so suggest things that it could be interpreted as asking.
2) Someone else has already given the main answer, so, rather than repeat them, I offer alternatives (my other option would be to post nothing)
3) I consider the main answer to be sufficiently obvious or well known that, rather than simply posting an answer I've remembered from elsewhere, I'll look for something new to say.
4) I want to show I know the answer without actually posting it - so post some cryptic reference to the answer (something I've also noticed Icarus doing in the past).

Speaking of Icarus, for his variation:
[hideb]If the chief wants to test you all fairly, you must be put into a totally symmetric situation when the blindfold is removed, so you must all have red or all have green spots. If you each have red spots, then you all know as soon as none of you put up your hands. If you each have green spots, then (in principle) you have to wait for the other two to fail to identify themselves before you can identify yourself. Therefore, you conclude that the chief would plan to put green spots on each of you.

Of course, this assumes that you don't expect the chief to think of this himself - if he does, and expects you to do so as well, then he could well plan to give each of you a red spot and wait to see who's smart enough to wait to find out which colour he's chosen to give you all.[/hideb]

Title: Re: Three Dots
Post by Icarus on Apr 4^th, 2005, 7:18pm

on 04/04/05 at 00:34:58, Speaker wrote:

No - my intent is that the chief is honest. All three of candidates have an equal chance. He really is testing to find out who is quickest on the uptake. But the respondent (you, if you insist on being in the riddle) is so much quicker on the uptake than the other two that he is able to deduce the actual color the chief will use (not just some condition on it) before the contest even begins.

Because this version is considerably subtler than the original, I've decided to give it its own thread (http://www.ocf.berkeley.edu/~wwu/cgi-bin/yabb/YaBB.cgi?board=riddles_medium;action=display;num=1112667358;start=0#0) in the Medium forum. Please direct any responses to that thread instead of this one. Thanks!

Title: Re: Three Dots
Post by Avo on Apr 5^th, 2005, 5:03pm

http://godfatherchat.proboards18.com