@khanacademy Please, correct if I'm wrong, but I think I found a mistake on this Brain Teaser. When you ask the truth toggler (the one who said no to the first question) who is NOT the truth teller, he is obligated to lie, right? So, he can simply say: everyone is not the truth teller, or there's no truth teller here. In this case, he would be lying and you could not be sure yet.
@TheOpposedMan That doesn't work because those answers do not correspond to the question asked. The ‘who’ implies a single person. “Everyone is not the TT” would not be a lie. It is true that everyone is not the TT. “There is no truth teller here” would indeed be a lie, but it does not fit to Q#2, because you ask ‘Who.’ The Toggler must answer the question with a statement regarding a single person.
@WoWDart Saying 'nobody is a truth teller' would made sense in the context of the question and at the same time it would be a lie. Imagine you asked the truth teller something similar - "Who is over 3 meters tall?" He would truthfully say - "nobody".
I´m not quite sure what kind of question are allowed and what answers the characters can give, but what if I asked one of them " who´s gonna respond to my question the same way as you do? ". A thruthteller would tell me the name/position/or piont at another thruthteller, while a liar shut name another liar, but (since he´s a liar) names a thruthteller.
regardless to their state, even if thruthteller himself theire nomination is a currently thruthteller who I can simply ask. -someone sees a probl
i got the answer within like 2 seconds but i had a different approach. q1 who would tell me the truth on my first question? to the same guy q2 who would tell me the truth on my second consecutive question? if its him both times, he's the truth teller. if any of the other choices change, that is the truth teller.
I don't think that's right! You started with 5 guys there, but your example only had 2 people. What if both the people you were asking questions to were togglers? Idk!!
I Came up with another solution myself, So Q#1 would be a fact question.lets say "What is the color of Milk?" now if you ask a Toggler he would lie/tell the truth. If he lies then you know hes gonna tell the truth next time.So you ask him Q#2 "Which guy is the TT?" done.If he tells the truth and says White,it might be the TT or a Toggler.Both ways you would then ask Q#2 "Who is a toggler?" If a toggler answers he would say "That guy" meaning the TT.If the TT answers he would say "All of those".
@reddishlu almost right, but it's failed in one aspect. If in this case, you asked a Truth-Teller "Who is a Toggler?" he wouldn't say "All of those", he could simply say "That guy is a Toggler", which would be totally true.
@TheOpposedMan haha i understand where you coming from. But i believe my answer is 100% Right :) We can ask other people what they think..so please anyone??
After a couple of minutes, I came up with a similar solution. Instead of asking, "Who is the truthteller?", I asked, "Are the others all togglers?". If yes, I ask them, "Who is the truthteller?", and they'll tell me the truth. If the answer no, I ask them, "Who is the toggler?",and they'll tell me who the truthteller is. It's interesting how a solution could be worded differently. I thought I was wrong at first when I unpaused the video. Anyways, the brainteaser was pretty easy. :)
Suppose "B" is the truther and you ask "A" "Are the others all togglers?". He tells truth and says "no". So then you ask .. "Who is the toggler?",and he lies and says "myself, B and C are all togglers". Sals answer is flawed and so is yours. ( P.S. there is a valid answer to this puzzle but no one seems to be able to get it )
@TechN9ician2159 You will know when you ask the second time. The truther would tell you the same answer. If the toggler told you the truth, he would have already identified the truther. If not, he would the second time you ask.
@ninawth Okay, say he identifies the other four as togglers the first time. If he's the truther, he'll tell you the same answer the second time you ask him. If he's a toggler, then the first time is a lie and the second time, he'd have to identify him and three others as togglers. That would give you the truther. He could have also answered with the truth the first time, thus identifying him as a toggler, while still revealing who the truther is. You wouldn't even have to ask the second time.
@rchangmh What ? Suppose "B" is the truther and you ask "A" "who are togglers? He lies and says "Me, B, D and E" are togglers. So you will now conclude that "C" is the truther !! No one has been able to get this riddle with 2 questions !! Net alone
Could you solve this in one question? What if you ask "Which of you will occasionally lie to me?"
The truthteller or currently truthful toggler would tell you each of the four togglers, so the unnamed one is the truthteller. A lying toggler could only tell you the truthteller because to tell you any of the togglers would be true. This answer does assume that a lying truth teller would avoid any partial truth.
@thestrawberrycrush Yes but the trick is to come up with a solution where the lying truthteller gives you a partial truth response and you can still find the truther.
@EagleFeatherful. I don't know that the video poster wants the answer in the comments but if you finnish the video to see the answer that is exactly what I came up with. Hence the comment I posted.
@ushouldbacomedian The answer by Sal in the video has been challenged by several people including myself. Sals answer is flawed because he assumes that a lieing toggler will answer the exact opposite of the truth. If your answer is the same as Sals then your answer is also flawed. There is another answer which works and gets around this flaw.
What if you ask twice to the same person "who are the togglers?". If he is a toggler he'll change his aswer the second time you ask him and the one person that wasn't a toggler in one of his answers will be the truthteller. If it is the truthteller he will always say that he his the truthteller. If there is any flaw in my theory I appologize, I spent about 10min. thinking about this.
Sure he can lie and say that he is a toggler ! If he answers ..." me , B, C and D are togglers" and in fact "C" is a truther, then he has lied ! What people are overlooking is that part of his answer can be truthful and part of his answer can be a lie which makes the complete answer a lie. ( my solution allows for this )
It took me about 3 minutes to find out you need a reciprocal question for the two different situations after that it took another 5 minutes to find out which one would apply to any given situation
@ilikeknifing777 so you ask Q1 to "A" , are you a toggler and he says yes. which is a truthful toggler. Now you ask him "which one of you isn't the truthteller " ? And he lies to you and replies " we are all togglers, there are not truthtellers here " !( your solution is flawed ). I have a solution which gets around this problem.
@EagleFeatherful the question is indeed rather impossible if you take it that the togglers lie in whatever way they want, because the proposed solution sets it that the togglers tell the direct opposite truth in their lie format.
@ilikeknifing777 If we accept Sals definition of the puzzle , nowhere does Sal define that togglers must answer the direct opposite. The flaw is that in his solution he assumes that togglers will lie the direct opposite. There is a solution ( it is not impossible ) that allows togglers to lie any way they want to.
@EagleFeatherful Your second and ultimate question in the solution is:
" I know that between "B, C and D that they might all be togglers but nonetheless tell me of those 3, who 2 and only 2 togglers are ?" They could simply lie and say none or all or all of them, because your following the pretense they are answering in the direct opposite truth. Because based off of what you said they could lie to the question with any answer other than the truth. So they can lie their way out of it, same flaw.
@ilikeknifing777 suppose E is truther. ask "A" Q1 who is truther ? : He tells truth and says "E". Now ask "A" Q2 : He lies and says "none" ( or all of them). He is clearly lieing therefore his first answer was truhtful and so "E" is the truther. If he lied about "E" at Q1 ( ie suppose "B" is truther) Ask Q2 he must answer truthful so he says "C & D" . Now I know "B" is truther. They cannot lie their way out.
@EagleFeatherful I just had a rather momentous epiphany, if the togglers could lie in anyway imaginable when lying, couldn't the togglers/truthteller tell the truth in anyway they want. So if you ask them who is a toggler out of A, B, C, D (let's say they're all togglers) they could reply truthfully that A is a toggler.So instead of telling the whole truth ,they tell a part of the truth.
@ilikeknifing777 Ahhhhh .... excellent observation ! When I give this puzzle I stipulate that the truther ( or toggler telling the truth ) must answer the truth the whole truth and nothing but the truth, and cannot be evasive in any way shape or form.
But the sky is the limit for a lying toggler. Both of which I think are within fair play for the puzzle. ( ie within the spirit of the puzzle )
You ask every single person (as a general question, to the five people) , "what is one plus one?" (1+1) and all of them will answer either correctly or incorectly. On the second question you ask again, what is one plus one? The truth-teller will always be the person who answers correctly twice.
Please note:
You can actually do this with a lot of different questions as long as their is only one possible solution. Taking the videos example, the truth-teller will say his name*2.
@jonnylolz6554 you cant ask them all at once the Q. you ask only one person at a time(max two qu), so your's method does'nt catch with those conditions.
It's not flawed, because if you're asking one to select the four togglers, and it's an untruthful answer, then he MUST put himself as a non-toggler (he can't group himself with the togglers if he's lying about it). Therefore, if the answer changes when you ask him twice, the odd man out that doesn't include the toggler you asked will be the truthteller.
If you ask person "A" to tell you who the four togglers are and suppose the truther is "B", then he could lie and say ... Me , B , C and D are togglers ( is a lie) , or he can say "B" , "C" "D" and "E" are togglers ( is a lie ). He could say ... How can I name 4 togglers when in fact all 5 of us are togglers ! ( is also a lie ). You have failed to convince me that your answer is not flawed.
Come to think of it, the toggler on lie mode could theoretically include himself in the lie, if in the group of four he listed he had the truth teller. Darn.
I like mine because you don't have to switch based on the initial answer. If you ask twice, and their answer is the same answer, they are the truth teller. If you ask twice, and their answer is not the same answer, then they are a toggler. And for the question where they include themselves in the group of togglers, the odd person out has to be the truth teller.
Who are the four togglers? If you ask happen to ask the truth teller, he will have the same answer twice. If you ask a toggler, the answer will be different one of the times. Whoever is left out on his honest answer that includes himself is the truth teller.
A diff teaser. Five liars 1 truth teller. Gold behind one door. Death behinfd the other. What question do you ask to find the door with the gold? 1 question.
Problem Cru-- Your solution doesn't work. If you get a toggler you will get one truthful answer, and one which isn't. You won't have the ability to distinguish between them. My set up below allows the distinction by separating who will tell the truth and who will lie to the second question.
Spoiler: First question: Are you a toggler? If yes, the person is a toggler, and in truth mode, meaning for second answer will be a liar. Ask which person is not a truth teller. Since he will lie, he will pick the truth teller, and you have your answer.
Or the answer to the first question is "No" which means you either have the truth teller or a a toggler in lie mode. Either way, the next answer will be truthful. So you simply ask which person is the truth teller, and you have the answer.
@WHITEMANDINGO Suppose "B" is a truther and you ask "A", Are you a toggler? he answers Yes. But then you ask " which person is not a truth teller ? He answers " A , B and C are not truthtellers. He lied and you dont know who the truther is.
@Cruciatum Suppose "B" is a truther and you ask "A", Which people wouldn't always speak truth? ( toggler lieing says ) A, B C and D would not always tell the truth. Then
you ask him again ,,, Which people wouldn't always speak truth? He now tells you truthfully A, C, D and E would not always tell the truth. So who is the truther, B or E ?
When i figured this out (in maybe a minute or so) I could only come up with a 1 question solution. My solution was to ass "Who here is not the truthteller?"
If they answer multiple people, then the odd one out would be the truthteller. This is the case where they told the truth.
If they answer only one person, that person is the truthteller, as they are obviously lying when you know multiple people are not truthtellers.
@Kim2bach You are saying you solved this one while drunk ? No one that I have seen has proposed a viable solution when they are sober net alone drunk ! I find your comment very hard to believe !
@odtandbuddies Suppose "B" is a truther and you ask "A", Are you a truther? he answers No ( truthful toggler) . then you ask " who are the people that lie? He answers " A , B and C all lie. . He lied and you dont know who the truther is.
@nikiTheMighty If you pick a toggler who is lying, he could simply give you the name of 3 togglers and the truthteller. His overall statement would be a lie due to how the 'and' operator works in logic. Thus you couldn't stop at 1 question and know with 100% certainty who the TT was starting that way.
I maintain that Sals solution is flawed. If you ask "A" : Are you the truthteller ?
And he responds "No", and then you ask "A" - Who is not the truthteller ?
He can respond A, B, C and D are not truthtellers - and as long as either B, C or D is the truther then he would be lying and you will not know who the truther is. My solution ( posted below ) works and is still unchallenged.
1. Which of these people ALWAYS lie? If he mentions anyone, then he's lying. Then you simply ask him who's the truthteller. If he says no one, then you ask him who is NOT the truthteller. He has to lie so he points out the truthteller. Thumbs up for alternate response!!!
@philster00700 You ask him who is not the truthteller and he answers "A, B , C & D are not the truth teller But he is lying - so who is the truther ? All you know is that if you asked "A" then "A" and "E" are togglers
but B, C or D could be a truther. Your solution is flawed.
@EagleFeatherful No, I said "who ALWAYS LIES?" (there is no such thing), therefore if he mentions anyone, then he is lying. Then you ask him who is the truthteller, and he has to say the truth. If he answers NO ONE to the initial question, then he is the truthteller. It's not flawed, you just misunderstood it.
@philster00700 What you are saying makes no sense. If he answers NO ONE to your initial question, then he is NOT necessarily the truthteller as you are now stating, he could be a truthful toggler. I think it is you that misunderstands the problem !! Your solution is now flawed on 2 counts.
@EagleFeatherful Okay I get what you are saying, he can be a truthful toggler if he answers NO ONE, but then you simply ask him who is NOT the truthteller and he HAS to lie so he'll point him out. Does that make sense? or am I missing something still, sorry for the confusion. I'm pretty sure it's not flawed
@philster00700 So now we are back to my original comment from last day. Suppose you pose both questions to "A" and suppose "B" is a truthteller and you ask "A" (Q2) who is NOT the truthteller ? He answers "A, B , C & D are not truth tellers ! ( But he is lying to you cos "B" indeed IS a truthteller ) . What you are missing is that when a lying toggler lies, not everything he tells you must be false. If one part of his answer is a lie , his whole answer becomes a lie.
@EagleFeatherful Ques 1. Who ALWAYS lies? Ans1. A B C.....and doesn't matter who Ans2. No one. Ques 2 to Ans1. Who is the trutheller? Ans. HIM, the truthtellr (whoever he may be) Ques 2 to Ans2. Who is NOT the trutellr? Ans. (okay I get what you are saying, he can point out only two people here for example, which would leave me stumped). Thanks for the insight! sorry if I caused chaos.
@EagleFeatherful: S/He does not need to answer a 100% but s/he has to give the best s/he can. lets say we have a, b, c, d, e where we ask c and the truthteller is e. c's false answer will be a, b, d, e. this is not completely false but still is false. and her/his true answer will be a,b,c,d. where he swapped c for e. and since now we know s/he is a toggler the tt will be e.
I will look for your solution also and see how you have done it.
@MO273 I processed it similarly. with both questions being what are the truth and false values of every other one on this iteration.
if the two sets are opposite for each, then the one you asked is the truth teller. If you are asking a toggler then the values would remain the same for everyone except the truth teller, i think. I haven't processed this for very long at all.
@MO273 He is not required to answer 100% opposite. "A" for example can answer Q#1 with "A, B, C & D are all togglers" and he answers Q#2 with "A, B, C & E are all togglers "
and you do not know whether D or E is the toggler. Your solution is not complete. I have posted a complete solution here a few weeks ago. Take a look.
If he answers the same both of the times, it means he is telling the truth, and he is the truth teller. If he changes the answer, you will know if he was telling the truth or lying on the first question by looking if he included himself in the first question when you asked who the togglers are. If he did, he was telling the truth and the guy he exluded is the TT. If not, the guy he exluded in the 2. Q is the TT
@fosheimdet Nowhere in Sals description of the puzzle does he say that a lying toggler must provide a lie that is totally 100% opposite of the truth. Several people here ( including myself ) are arguing that a lying toggler can give an answer that is partially true and partially false and furthermore a lying togglers answer does not need to be a complete answer. In your answer the toggler escapes easily Q1 he answers A, B , C , D, Q2 he answers A, C, D, E. Is the toggler B or E ?
Hmm... I would ask one by random if they're the truthteller. Then I would ask the same person if "he's the truthteller". "he"being another random person. well thats what I think. Time to play the video now to see if I'm right!
I didn't watch the solution yet but I don't see how this riddle is so hard. I found a way to solve it with asking only one question.
"Who in this room is a toggler?" or "Who is in this room is the truth teller?" One of those questions.
If you ask "Who in the room is a toggler?". If he responds with four people, the other person is the truth teller and if he responds with one person, then that person is the truth teller. And it works the same with the other question, only the other way around.
@elidrissii Please point out any flaw in my solution, I didn't watch the solution of the video yet and want to figure it out by myself but I am wondering if my first solution is right.
@elidrissii if im a toggler and u ask me ''who in this room is a toggler'' i could say (truth) i am a toggler or (lie) he (truthteller) is a toggler... Your question doesnt require me to name all the togglers
Just say what is 2+2 and then if they are saying a lie make them say who's the truthteller and if they are saying truth make them say who is absolutely not the truthteller
He answers 4 the 1st time, now you ask who is absolutely not the truthteller. And he says B & C are absolutely not the truthteller ! ( but he is lying - in fact B is a truthteller - and so your solution does not work )
My solution was the first question would be : is your answer going to be the same as this answer if i ask this question again?
Liar would say yes because the answer is not going to be the same so he would have to lie, if he told the truth he would say no because the answer is not the same, and then u ask the second question who is the truthteller/who is not the truthteller
@ceosir711 You mean ... Q1 = Will your 2nd answer be the same as your 1st answer if I ask you the same question twice ? Suppose "E" is the truther, and you ask Q1 to "A" (who is a truth toggler) and he answers "NO", then you ask him, who is not the truthteller ? He answers "B, C & E are not truth tellers" - ( but he is lying ). If you ask him who the truther is , he can say " I am the truther ! " but he is lying, so your answer I think has a problem
@EagleFeatherful Suppose you ask the first question to A, who is truthful toggler, he will answer with the correct truthteller, but you won't know if he is actually telling the truth or not, what do u do from there?
@gunking1949 suppose E is the truther and "A" answers "E" because "A" is a truthful toggler.
Now I ask "A" Q2 - " I know that between "B, C and D that they might all be togglers but nonetheless tell me of those 3, who 2 and only 2 togglers are ?" ( All 3 are togglers - right ? ) So "A" cannot answer BC, nor BD nor CD because he must lie - so he says something like : "none of those 3 are togglers ! " Now I know he told the truth about E - so E is the truther in this case.
My solution was to ask one person the same question twice : What is each person, a truthteller or a toggler?
If that person is a toggler, they will give me a different answer each time.
a = truthteller b = toggler
Ex: truth toggler says: bbbab then aaaba.
lie toggler says: aaaba then bbbab.
truthteller says: bbbab then bbbab.
So even if I happen to ask a toggler, I can still figure out who is the truth teller by seeing which person was the only one of their type in each answer.
Your solution will not work. A truth toggler can say bbbab followed by bbbba as his answers. So who is the truther ? You dont know. When he lies, all he has to do is make one part of his answer a lie.
Right. It seems to be agreed by most that the sky is the limit for a lying toggler.
If you asked him who the togglers are and he is lying , he could reply
" there are no togglers here at all ! " Take a peak at my solution. It works, and it allows for a lying toggler to be as creative as he likes with his lie.
I mean, the first round of questions would really be enough, if done this way, because the second round would just give the 'mirrored' answer. (check your own post: first round, truth toggler says bbbab, truthteller says bbbab, liar says aaaba. You can just pick the odd one out.)
My solution is to ask a random guy who are liars. Supposing he is lying he would have to say only guy and that would answer everything. But if he picks 3 guys, then he is telling the truth, the only guy would therefore would be the tt.
@paulyeo23 Suppose you ask person A ( and A is a toggler ) who are liars ?
If he is lying, he can tell you that persons A, C, D & E are all togglers.when in fact person E is a truther.( so he is lying - right ? ) so now what will you ask him ? If you ask him again he will tell you the truth this time . He will answer A, B, C and D which is truthful but then you will not know whetther B or E is a truther.
My answer is complete and it works. ( 4 part solution below )
Part 4, in my solution, I am proposing that when a toggler lies he can dream up any thing he likes, I pose no restriction, he can be as evasive as he can be, but the key is that if he told the truth the first time, he must find a way to lie to my second question
Part 3 to my solution. But suppose he answers "E" the first time and he was telling the truth. (ie "E" is the truther) then I ask him my "B,C, D" question, and he must lie. Go ahead ! Come up with your best but it must be a lie. How about "none of those 3 are togglers !". I can now declare "E" to be the truther.
If however his answer to Q1 is "B" then in my second question. instead of asking about "BC & D" , I ask about "C, D and E", and likewise if he answers "C" or "D"
Part 2 to my solution. If his answer to question 1 was "A - ME ! " then when I ask him the same question again, he must direct me to the truther, ( if he i a toggler, then he lied the first time - now he must be truthful)
But suppose he answers "E" the first time and he was lieing. (ie "D" is the truther) then I ask him my "B,C, D" question, and he will be truthful and answer "B & C" Now I can declare that "D" is the truther.
Here is my solution. ( they are lined up left to right, "A" through "E")
I ask "A", who is the truther ? If he answers "A", then I ask him again
who is the truther ? Whatever his answer is, he will be directing me to the truther.
But if his answer to question 1 was for example "E", then I pose this second question also to "A" :: " I know that between "B, C and D that they might all be togglers but nonetheless tell me of those 3, who 2 and only 2 togglers are ?
hahahh so much fun.
rakib567 3 hours ago
@khanacademy Please, correct if I'm wrong, but I think I found a mistake on this Brain Teaser. When you ask the truth toggler (the one who said no to the first question) who is NOT the truth teller, he is obligated to lie, right? So, he can simply say: everyone is not the truth teller, or there's no truth teller here. In this case, he would be lying and you could not be sure yet.
TheOpposedMan 5 days ago
@TheOpposedMan That doesn't work because those answers do not correspond to the question asked. The ‘who’ implies a single person. “Everyone is not the TT” would not be a lie. It is true that everyone is not the TT. “There is no truth teller here” would indeed be a lie, but it does not fit to Q#2, because you ask ‘Who.’ The Toggler must answer the question with a statement regarding a single person.
WoWDart 4 days ago
@WoWDart I get it, but it does fit to Q#2!
TheOpposedMan 4 days ago
@WoWDart Saying 'nobody is a truth teller' would made sense in the context of the question and at the same time it would be a lie. Imagine you asked the truth teller something similar - "Who is over 3 meters tall?" He would truthfully say - "nobody".
stenlis 4 days ago
It took you 4 minutes to explain what a toggler is. Please hurry the fuck up.
Ultraman221 1 week ago in playlist Brain Teasers
@Ultraman221 This is kind of a problem with all of his videos. I'm glad to see someone agree for once.
duhboss1 6 days ago
I´m not quite sure what kind of question are allowed and what answers the characters can give, but what if I asked one of them " who´s gonna respond to my question the same way as you do? ". A thruthteller would tell me the name/position/or piont at another thruthteller, while a liar shut name another liar, but (since he´s a liar) names a thruthteller.
regardless to their state, even if thruthteller himself theire nomination is a currently thruthteller who I can simply ask. -someone sees a probl
contourplot 1 week ago
@contourplot shut ..... should
spelling mistakes... you can keep them
contourplot 1 week ago
i got the answer within like 2 seconds but i had a different approach. q1 who would tell me the truth on my first question? to the same guy q2 who would tell me the truth on my second consecutive question? if its him both times, he's the truth teller. if any of the other choices change, that is the truth teller.
sheepwshotguns 2 weeks ago
@sheepwshotguns *who all would tell me
had to fix that
sheepwshotguns 2 weeks ago
@sheepwshotguns your answer is stupid and wrong, when lying he could say any of the four togglers is the truth teller
jonopalmer11 1 week ago
@sheepwshotguns and how can you distinguish candidate 1 (nominated after q1) or candidate 2 as the truthteller
contourplot 1 week ago
I don't think that's right! You started with 5 guys there, but your example only had 2 people. What if both the people you were asking questions to were togglers? Idk!!
Stevesrssrssrs 2 weeks ago
I Came up with another solution myself, So Q#1 would be a fact question.lets say "What is the color of Milk?" now if you ask a Toggler he would lie/tell the truth. If he lies then you know hes gonna tell the truth next time.So you ask him Q#2 "Which guy is the TT?" done.If he tells the truth and says White,it might be the TT or a Toggler.Both ways you would then ask Q#2 "Who is a toggler?" If a toggler answers he would say "That guy" meaning the TT.If the TT answers he would say "All of those".
reddishlu 2 weeks ago
@reddishlu almost right, but it's failed in one aspect. If in this case, you asked a Truth-Teller "Who is a Toggler?" he wouldn't say "All of those", he could simply say "That guy is a Toggler", which would be totally true.
TheOpposedMan 2 weeks ago
@TheOpposedMan "Who is a Toggler?" Implies 'who out of these guys is a Toggler' ;)
reddishlu 2 weeks ago
@reddishlu the challenge is to be 100% sure about who is the Truth-Teller. You made it very nice, but it's not 100% right.
TheOpposedMan 2 weeks ago
@TheOpposedMan haha i understand where you coming from. But i believe my answer is 100% Right :) We can ask other people what they think..so please anyone??
reddishlu 2 weeks ago
@reddishlu haha i think we don't have to ask anyone, one of the greatest virtue in science is to find your own mistake!
TheOpposedMan 2 weeks ago
After a couple of minutes, I came up with a similar solution. Instead of asking, "Who is the truthteller?", I asked, "Are the others all togglers?". If yes, I ask them, "Who is the truthteller?", and they'll tell me the truth. If the answer no, I ask them, "Who is the toggler?",and they'll tell me who the truthteller is. It's interesting how a solution could be worded differently. I thought I was wrong at first when I unpaused the video. Anyways, the brainteaser was pretty easy. :)
BlossomSujuFan 3 weeks ago
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@BlossomSujuFan
Suppose "B" is the truther and you ask "A" "Are the others all togglers?". He tells truth and says "no". So then you ask .. "Who is the toggler?",and he lies and says "myself, B and C are all togglers". Sals answer is flawed and so is yours. ( P.S. there is a valid answer to this puzzle but no one seems to be able to get it )
EagleFeather972 2 weeks ago
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whaadis 3 weeks ago
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whaadis 3 weeks ago
I figured this out right when the question was asked and I thought I was wrong and took my time then played and I was right~
iluvuknow 3 weeks ago
I worked this out straight away, then I thought no thats too easy spent a whole day thinking about it then found out I was right :(
HeLpErNaThAn 4 weeks ago
@HeLpErNaThAn and @iluvuknow I had the same thing!
ninawth 3 weeks ago
@HeLpErNaThAn
See my response to Marcell.
EagleFeather972 2 weeks ago
@HeLpErNaThAn The puzzle is not as easy as people are thinking.
I still have not seen a valid answer. See my response to Marcello as an example.
EagleFeather972 2 weeks ago
i manage to solve this one by myself exactly like Sal, that means i'm good.
marcellohro 4 weeks ago
@marcellohro
But Sals solution has a flawed. Suppose "B" is truther and you ask "A" Who is truther ?
He truthfully says no. Then you ask "who is not the truthteller " ? He lies and says neither "B, C & D are truthers.- and you are messed
EagleFeather972 2 weeks ago
i love your videos Susan
boxerek123 4 weeks ago
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saharSA1 1 month ago
but what if the lie was the same thing everytime. a lie is a lie no matter how many times they said it so....
lucymydog1995 1 month ago in playlist More videos from khanacademy
You could ask "which four are togglers?" twice to one person.
rchangmh 1 month ago
@rchangmh That's what I came up with too.
philnoll 1 month ago
@rchangmh how do you know whether he said the truth or lied the first time
TechN9ician2159 1 month ago in playlist Khan Academy Brain Teasers!
@TechN9ician2159 You will know when you ask the second time. The truther would tell you the same answer. If the toggler told you the truth, he would have already identified the truther. If not, he would the second time you ask.
rchangmh 1 month ago
@rchangmh
I dont understand your solution
EagleFeather972 2 weeks ago
@rchangmh No, sorry. I don't think that would work, because then you don't know when he's lying and when he's telling you the truth.
ninawth 3 weeks ago
@ninawth Okay, say he identifies the other four as togglers the first time. If he's the truther, he'll tell you the same answer the second time you ask him. If he's a toggler, then the first time is a lie and the second time, he'd have to identify him and three others as togglers. That would give you the truther. He could have also answered with the truth the first time, thus identifying him as a toggler, while still revealing who the truther is. You wouldn't even have to ask the second time.
rchangmh 3 weeks ago
@rchangmh What ? Suppose "B" is the truther and you ask "A" "who are togglers? He lies and says "Me, B, D and E" are togglers. So you will now conclude that "C" is the truther !! No one has been able to get this riddle with 2 questions !! Net alone
one question !! You have more work to do !
EagleFeather972 2 weeks ago
just ask them r u male or female
PineCocunut 1 month ago
yes! i actually figured it out :D
took me like a day
i was in the middle of English class and it came to me
ruru6374 1 month ago
Could it be solved in 1 question by saying "Who would the truth sayer say they are not?"
Desertbiker125 1 month ago
If I told you that I'm a toggler, would you believe me, or would you think I'm lying?
Justinfh2point0 1 month ago
Could you solve this in one question? What if you ask "Which of you will occasionally lie to me?"
The truthteller or currently truthful toggler would tell you each of the four togglers, so the unnamed one is the truthteller. A lying toggler could only tell you the truthteller because to tell you any of the togglers would be true. This answer does assume that a lying truth teller would avoid any partial truth.
thestrawberrycrush 1 month ago
@thestrawberrycrush Yes but the trick is to come up with a solution where the lying truthteller gives you a partial truth response and you can still find the truther.
( there is a solution )
EagleFeatherful 1 month ago
@EagleFeatherful. I don't know that the video poster wants the answer in the comments but if you finnish the video to see the answer that is exactly what I came up with. Hence the comment I posted.
ushouldbacomedian 1 month ago
@ushouldbacomedian The answer by Sal in the video has been challenged by several people including myself. Sals answer is flawed because he assumes that a lieing toggler will answer the exact opposite of the truth. If your answer is the same as Sals then your answer is also flawed. There is another answer which works and gets around this flaw.
EagleFeatherful 1 month ago
never mind
zzzduelist 1 month ago
ALTERNATE SOLUTION:
ask one of them "point out the four togglers."
then, approach the FIFTH person they did not point out (it could be the very same person) and ask them "who is the truth teller?"
zzzduelist 1 month ago
@zzzduelist Suppose "B" is the truther. You ask "A" -- "point out the four togglers"
"A" says ... me . B . C & D are the togglers ! ( he is lieing ). So then you ask "E",
Who is the truther ? "E" also lies and says "D" !
I think you have misunderstood the problem.
EagleFeatherful 1 month ago
I got it right away! I can't believe it...
ushouldbacomedian 1 month ago
@ushouldbacomedian
what is your solution ? I have yet to see a viable solution from anyone.
( except mine ! )
EagleFeatherful 1 month ago
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sagirius19 1 month ago
What if you ask twice to the same person "who are the togglers?". If he is a toggler he'll change his aswer the second time you ask him and the one person that wasn't a toggler in one of his answers will be the truthteller. If it is the truthteller he will always say that he his the truthteller. If there is any flaw in my theory I appologize, I spent about 10min. thinking about this.
BazicShotz 1 month ago
@BazicShotz You ask "A" Q1 - who are the togglers?". He replies ..." me , B, C and D are togglers". You ask "A" Q2 - who are the togglers?".
He replies ..." me , B , C and E" are togglers". So is the truther "E" or "D" ?
If you want to see a solution that works , check out my solution from a few weeks ago.
EagleFeatherful 1 month ago
@EagleFeatherful if he lies he cant say that he is the toggler
BazicShotz 1 month ago
@BazicShotz
Sure he can lie and say that he is a toggler ! If he answers ..." me , B, C and D are togglers" and in fact "C" is a truther, then he has lied ! What people are overlooking is that part of his answer can be truthful and part of his answer can be a lie which makes the complete answer a lie. ( my solution allows for this )
EagleFeatherful 1 month ago
It took me about 3 minutes to find out you need a reciprocal question for the two different situations after that it took another 5 minutes to find out which one would apply to any given situation
ilikeknifing777 2 months ago
@ilikeknifing777
So what is your proposed solution ?
EagleFeatherful 1 month ago
@EagleFeatherful question 1 are you a toggler
if yes then ask which one of you isn't the truthteller ,if no ask who is the truthteller
ilikeknifing777 1 month ago
@ilikeknifing777 so you ask Q1 to "A" , are you a toggler and he says yes. which is a truthful toggler. Now you ask him "which one of you isn't the truthteller " ? And he lies to you and replies " we are all togglers, there are not truthtellers here " !( your solution is flawed ). I have a solution which gets around this problem.
EagleFeatherful 1 month ago
@EagleFeatherful the question is indeed rather impossible if you take it that the togglers lie in whatever way they want, because the proposed solution sets it that the togglers tell the direct opposite truth in their lie format.
ilikeknifing777 1 month ago
@ilikeknifing777 If we accept Sals definition of the puzzle , nowhere does Sal define that togglers must answer the direct opposite. The flaw is that in his solution he assumes that togglers will lie the direct opposite. There is a solution ( it is not impossible ) that allows togglers to lie any way they want to.
EagleFeatherful 1 month ago
@EagleFeatherful and your solution has the same flaw.
ilikeknifing777 1 month ago
@ilikeknifing777 How does my solution have the same flaw ?
EagleFeatherful 1 month ago
@EagleFeatherful Your second and ultimate question in the solution is:
" I know that between "B, C and D that they might all be togglers but nonetheless tell me of those 3, who 2 and only 2 togglers are ?" They could simply lie and say none or all or all of them, because your following the pretense they are answering in the direct opposite truth. Because based off of what you said they could lie to the question with any answer other than the truth. So they can lie their way out of it, same flaw.
ilikeknifing777 1 month ago
@ilikeknifing777 suppose E is truther. ask "A" Q1 who is truther ? : He tells truth and says "E". Now ask "A" Q2 : He lies and says "none" ( or all of them). He is clearly lieing therefore his first answer was truhtful and so "E" is the truther. If he lied about "E" at Q1 ( ie suppose "B" is truther) Ask Q2 he must answer truthful so he says "C & D" . Now I know "B" is truther. They cannot lie their way out.
EagleFeatherful 1 month ago
@EagleFeatherful I just had a rather momentous epiphany, if the togglers could lie in anyway imaginable when lying, couldn't the togglers/truthteller tell the truth in anyway they want. So if you ask them who is a toggler out of A, B, C, D (let's say they're all togglers) they could reply truthfully that A is a toggler.So instead of telling the whole truth ,they tell a part of the truth.
ilikeknifing777 1 month ago
@ilikeknifing777 Ahhhhh .... excellent observation ! When I give this puzzle I stipulate that the truther ( or toggler telling the truth ) must answer the truth the whole truth and nothing but the truth, and cannot be evasive in any way shape or form.
But the sky is the limit for a lying toggler. Both of which I think are within fair play for the puzzle. ( ie within the spirit of the puzzle )
EagleFeatherful 1 month ago
@EagleFeatherful true because in that case it would be extremely difficult.
ilikeknifing777 1 month ago
Here's my answer:
You ask every single person (as a general question, to the five people) , "what is one plus one?" (1+1) and all of them will answer either correctly or incorectly. On the second question you ask again, what is one plus one? The truth-teller will always be the person who answers correctly twice.
Please note:
You can actually do this with a lot of different questions as long as their is only one possible solution. Taking the videos example, the truth-teller will say his name*2.
jonnylolz6554 2 months ago
@jonnylolz6554 you cant ask them all at once the Q. you ask only one person at a time(max two qu), so your's method does'nt catch with those conditions.
almogz 1 month ago
@EagleFeatherful
It's not flawed, because if you're asking one to select the four togglers, and it's an untruthful answer, then he MUST put himself as a non-toggler (he can't group himself with the togglers if he's lying about it). Therefore, if the answer changes when you ask him twice, the odd man out that doesn't include the toggler you asked will be the truthteller.
haewoodable 2 months ago
@haewoodable
If you ask person "A" to tell you who the four togglers are and suppose the truther is "B", then he could lie and say ... Me , B , C and D are togglers ( is a lie) , or he can say "B" , "C" "D" and "E" are togglers ( is a lie ). He could say ... How can I name 4 togglers when in fact all 5 of us are togglers ! ( is also a lie ). You have failed to convince me that your answer is not flawed.
EagleFeatherful 1 month ago
hd hy yar
775shahrukh 2 months ago
toggler is a weird name! wonder where he got it
wildwood168 2 months ago
Come to think of it, the toggler on lie mode could theoretically include himself in the lie, if in the group of four he listed he had the truth teller. Darn.
anaMovies 2 months ago
@anaMovies That is the problem ! But I have proposed a solution that gets past that block - and works !
EagleFeatherful 2 months ago
Darn character limits...
I like mine because you don't have to switch based on the initial answer. If you ask twice, and their answer is the same answer, they are the truth teller. If you ask twice, and their answer is not the same answer, then they are a toggler. And for the question where they include themselves in the group of togglers, the odd person out has to be the truth teller.
anaMovies 2 months ago
Spoilers.
I've got one that is the same question twice.
Who are the four togglers? If you ask happen to ask the truth teller, he will have the same answer twice. If you ask a toggler, the answer will be different one of the times. Whoever is left out on his honest answer that includes himself is the truth teller.
Let me write it out.
Hey Person A, who are the four togglers?
Person A: They are B, C, D and E.
Hey Person A, who are the four togglers?
Person A: They are me, B, D and E.
anaMovies 2 months ago
@anaMovies Hey Person A, who are the four togglers? Person A: They are me B, C, and E. Hey Person A, who are the four togglers?
Person A: They are me, B, D and E.
Who is the truther ? It is either C or D but you dont know who so your answer is flawed.
EagleFeatherful 2 months ago
Where can i find brain teasers???
intro06 2 months ago in playlist More videos from khanacademy
i feel very accomplished right now =P
hellomynameiswho 2 months ago
i got it!!!. i didn't have to sleep on it for a day...man these things are awesome!!
HENRYLUI51 2 months ago
A diff teaser. Five liars 1 truth teller. Gold behind one door. Death behinfd the other. What question do you ask to find the door with the gold? 1 question.
WHITEMANDINGO 3 months ago
Problem Cru-- Your solution doesn't work. If you get a toggler you will get one truthful answer, and one which isn't. You won't have the ability to distinguish between them. My set up below allows the distinction by separating who will tell the truth and who will lie to the second question.
WHITEMANDINGO 3 months ago
Spoiler: First question: Are you a toggler? If yes, the person is a toggler, and in truth mode, meaning for second answer will be a liar. Ask which person is not a truth teller. Since he will lie, he will pick the truth teller, and you have your answer.
Or the answer to the first question is "No" which means you either have the truth teller or a a toggler in lie mode. Either way, the next answer will be truthful. So you simply ask which person is the truth teller, and you have the answer.
WHITEMANDINGO 3 months ago
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@WHITEMANDINGO Suppose "B" is a truther and you ask "A", Are you a toggler? he answers Yes. But then you ask " which person is not a truth teller ? He answers " A , B and C are not truthtellers. He lied and you dont know who the truther is.
EagleFeatherful 2 months ago
me and my dad came up with this:
1) are you the truth teller?
2) who are the people that lie?
odtandbuddies 3 months ago
@odtandbuddies damn never mind
odtandbuddies 3 months ago
Can we ask the same person twice: Which people wouldn't always speak truth?
If he lies the first time he'll poke out the person that always tells truth, or if he's telling the truth he'll tell about other 4 include himself?
could really do with 1 question there though, I suppose.. If we can ask something like this though, if they know anything about eachother..
Cruciatum 3 months ago
@Cruciatum Suppose "B" is a truther and you ask "A", Which people wouldn't always speak truth? ( toggler lieing says ) A, B C and D would not always tell the truth. Then
you ask him again ,,, Which people wouldn't always speak truth? He now tells you truthfully A, C, D and E would not always tell the truth. So who is the truther, B or E ?
You dont know and so your answer is incomplete.
EagleFeatherful 2 months ago
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When i figured this out (in maybe a minute or so) I could only come up with a 1 question solution. My solution was to ass "Who here is not the truthteller?"
If they answer multiple people, then the odd one out would be the truthteller. This is the case where they told the truth.
If they answer only one person, that person is the truthteller, as they are obviously lying when you know multiple people are not truthtellers.
Funkipotato 3 months ago
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Funkipotato 3 months ago
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BasicSpace42 3 months ago
I need more teasers... This is awesome... Finally, even when I'm drunk I exceed... Some tings you're good at, some you aren't...
Kim2bach 3 months ago
@Kim2bach You are saying you solved this one while drunk ? No one that I have seen has proposed a viable solution when they are sober net alone drunk ! I find your comment very hard to believe !
EagleFeatherful 3 months ago
I got this exact answer in about 10 minutes :D Very nice riddle bro, not heard it before :P
diabl2master 3 months ago
@diabl2master 10 minutes ? What is your solution ? I have seen only one complete solution to date.
Sals solution as proposed is flawed.
EagleFeatherful 3 months ago
@EagleFeatherful how about this one:
1) are you the truth teller?
2) who are the people that lie?
odtandbuddies 3 months ago
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@odtandbuddies Suppose "B" is a truther and you ask "A", Are you a truther? he answers No ( truthful toggler) . then you ask " who are the people that lie? He answers " A , B and C all lie. . He lied and you dont know who the truther is.
EagleFeatherful 2 months ago
My attempt at a one question solution.
Ask a random person:
"Show me the people who can lie."
-If you picked a TOGGLER who is telling the TRUTH, he will point to everyone except the truthteller.
-If you picked a TOGGLER who is LYING, he'll have no choice but to point to the truthteller.
-If you picked the truthteller, he will point out everyone except himself.
nikiTheMighty 3 months ago
@nikiTheMighty If you pick a toggler who is lying, he could simply give you the name of 3 togglers and the truthteller. His overall statement would be a lie due to how the 'and' operator works in logic. Thus you couldn't stop at 1 question and know with 100% certainty who the TT was starting that way.
in0eterminacy 3 months ago
I solved it but I posed the question "Who is the toggler first?". The rest of the questions were same. I guess it was pretty easy
shakilmujeeb 3 months ago
@shakilmujeeb But the solution is flawed and therefore so is your solution !
EagleFeatherful 3 months ago
Ask the whole group what 1+1 is. Then ask the whole group what 1+1 is. Whoever said 2 twice is the truthful one...
iamtheplauge 3 months ago
@iamtheplauge You can't ask the whole group a question.
elastichick2 3 months ago
I maintain that Sals solution is flawed. If you ask "A" : Are you the truthteller ?
And he responds "No", and then you ask "A" - Who is not the truthteller ?
He can respond A, B, C and D are not truthtellers - and as long as either B, C or D is the truther then he would be lying and you will not know who the truther is. My solution ( posted below ) works and is still unchallenged.
EagleFeatherful 4 months ago
1. Which of these people ALWAYS lie? If he mentions anyone, then he's lying. Then you simply ask him who's the truthteller. If he says no one, then you ask him who is NOT the truthteller. He has to lie so he points out the truthteller. Thumbs up for alternate response!!!
philster00700 4 months ago
@philster00700 You ask him who is not the truthteller and he answers "A, B , C & D are not the truth teller But he is lying - so who is the truther ? All you know is that if you asked "A" then "A" and "E" are togglers
but B, C or D could be a truther. Your solution is flawed.
EagleFeatherful 4 months ago
@EagleFeatherful No, I said "who ALWAYS LIES?" (there is no such thing), therefore if he mentions anyone, then he is lying. Then you ask him who is the truthteller, and he has to say the truth. If he answers NO ONE to the initial question, then he is the truthteller. It's not flawed, you just misunderstood it.
philster00700 4 months ago
@philster00700 What you are saying makes no sense. If he answers NO ONE to your initial question, then he is NOT necessarily the truthteller as you are now stating, he could be a truthful toggler. I think it is you that misunderstands the problem !! Your solution is now flawed on 2 counts.
EagleFeatherful 4 months ago
@EagleFeatherful Okay I get what you are saying, he can be a truthful toggler if he answers NO ONE, but then you simply ask him who is NOT the truthteller and he HAS to lie so he'll point him out. Does that make sense? or am I missing something still, sorry for the confusion. I'm pretty sure it's not flawed
philster00700 4 months ago
@philster00700 So now we are back to my original comment from last day. Suppose you pose both questions to "A" and suppose "B" is a truthteller and you ask "A" (Q2) who is NOT the truthteller ? He answers "A, B , C & D are not truth tellers ! ( But he is lying to you cos "B" indeed IS a truthteller ) . What you are missing is that when a lying toggler lies, not everything he tells you must be false. If one part of his answer is a lie , his whole answer becomes a lie.
EagleFeatherful 3 months ago
@EagleFeatherful Ques 1. Who ALWAYS lies? Ans1. A B C.....and doesn't matter who Ans2. No one. Ques 2 to Ans1. Who is the trutheller? Ans. HIM, the truthtellr (whoever he may be) Ques 2 to Ans2. Who is NOT the trutellr? Ans. (okay I get what you are saying, he can point out only two people here for example, which would leave me stumped). Thanks for the insight! sorry if I caused chaos.
philster00700 3 months ago
this is harder than anything Professor Layton has ever given me!
prettyreckless2700 4 months ago
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@EagleFeatherful: S/He does not need to answer a 100% but s/he has to give the best s/he can. lets say we have a, b, c, d, e where we ask c and the truthteller is e. c's false answer will be a, b, d, e. this is not completely false but still is false. and her/his true answer will be a,b,c,d. where he swapped c for e. and since now we know s/he is a toggler the tt will be e.
I will look for your solution also and see how you have done it.
MO273 4 months ago
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MO273 4 months ago
This is how I processed the solution: Ask anyone
Q#1. Who are the 4 togglers among you 5?
Q#2. Who are the 4 togglers among you 5?
If a truth teller both answers be the same.
If a toggler
False Statement: will name the truth teller in the list and not name himself.
True Statement: Will name himself and the other three but not the truth teller.
The person other than him that changes in his list is the truth teller.
MO273 4 months ago
@MO273 I processed it similarly. with both questions being what are the truth and false values of every other one on this iteration.
if the two sets are opposite for each, then the one you asked is the truth teller. If you are asking a toggler then the values would remain the same for everyone except the truth teller, i think. I haven't processed this for very long at all.
DLH112 4 months ago
@MO273 He is not required to answer 100% opposite. "A" for example can answer Q#1 with "A, B, C & D are all togglers" and he answers Q#2 with "A, B, C & E are all togglers "
and you do not know whether D or E is the toggler. Your solution is not complete. I have posted a complete solution here a few weeks ago. Take a look.
EagleFeatherful 4 months ago
Both Qs for on the same guy:
Q 1: Who are the togglers?
Q 2: Who are the togglers?
If he answers the same both of the times, it means he is telling the truth, and he is the truth teller. If he changes the answer, you will know if he was telling the truth or lying on the first question by looking if he included himself in the first question when you asked who the togglers are. If he did, he was telling the truth and the guy he exluded is the TT. If not, the guy he exluded in the 2. Q is the TT
fosheimdet 4 months ago
@fosheimdet Nowhere in Sals description of the puzzle does he say that a lying toggler must provide a lie that is totally 100% opposite of the truth. Several people here ( including myself ) are arguing that a lying toggler can give an answer that is partially true and partially false and furthermore a lying togglers answer does not need to be a complete answer. In your answer the toggler escapes easily Q1 he answers A, B , C , D, Q2 he answers A, C, D, E. Is the toggler B or E ?
EagleFeatherful 4 months ago
@EagleFeatherful Yes, I see the flaw now. Thanks.
fosheimdet 4 months ago
Hmm... I would ask one by random if they're the truthteller. Then I would ask the same person if "he's the truthteller". "he"being another random person. well thats what I think. Time to play the video now to see if I'm right!
aznboy4123 4 months ago
The question is, is Sal the truth teller?
khuja1owl 4 months ago
No one has challenged my solution yet !
Does that mean I win the prize ?
EagleFeatherful 4 months ago
I didn't watch the solution yet but I don't see how this riddle is so hard. I found a way to solve it with asking only one question.
"Who in this room is a toggler?" or "Who is in this room is the truth teller?" One of those questions.
If you ask "Who in the room is a toggler?". If he responds with four people, the other person is the truth teller and if he responds with one person, then that person is the truth teller. And it works the same with the other question, only the other way around.
elidrissii 4 months ago
@elidrissii Please point out any flaw in my solution, I didn't watch the solution of the video yet and want to figure it out by myself but I am wondering if my first solution is right.
elidrissii 4 months ago
@elidrissii if im a toggler and u ask me ''who in this room is a toggler'' i could say (truth) i am a toggler or (lie) he (truthteller) is a toggler... Your question doesnt require me to name all the togglers
1phenix9 4 months ago
@1phenix9 Well, what if I formulate it in a way to name everyone? I wouldn't see a reason why it wouldn't work.
elidrissii 4 months ago
@elidrissii You ask "A" who in the room is a toggler ? And the answer you get back is A, B, C & D
( but he is lieing - B is a truther ). You cannot solve this riddle with one question because if you are lied to you are snookered.
EagleFeatherful 4 months ago
what if they themselves didn't know who was the truth teller?
XtraXtraodinaire 4 months ago
@XtraXtraodinaire
For the sake of this riddle everyone here is assuming that they must all know who is who
EagleFeatherful 4 months ago
1st question: what would be your answer if i my previous question is"name all the persons who would never lie?"
2nd question : same as first question
sasiacp 4 months ago
@sasiacp
What if you ask "A" and he responds to question 1 with "Not C" and to your second question he
answers "not E" : what can you conclude ? In one case he has lied but in the other case he told you the truth.
EagleFeatherful 4 months ago
...... not even trying
AlphaMitts 4 months ago
Just say what is 2+2 and then if they are saying a lie make them say who's the truthteller and if they are saying truth make them say who is absolutely not the truthteller
mins332 4 months ago
@mins332
He answers 4 the 1st time, now you ask who is absolutely not the truthteller. And he says B & C are absolutely not the truthteller ! ( but he is lying - in fact B is a truthteller - and so your solution does not work )
EagleFeatherful 4 months ago
i have a better solution ,
pick up anyone and ask the second question first.
ask who is the truth teller? No matter if hes a toggler or a truthteller , the second time he will surely give the right answer to the same question
sankalp35 4 months ago in playlist Brain Teasers
@sankalp35 Whywould you assume that ?
You ask "A" - Who is the truthteller ? He responds "B"
You ask "A" again - Who is the truthteller ? He responds "E"
So who is the truther ? "B" or "E" ??
EagleFeatherful 4 months ago
Comment removed
fleshiq 4 months ago
Comment removed
fleshiq 4 months ago
My solution was the first question would be : is your answer going to be the same as this answer if i ask this question again?
Liar would say yes because the answer is not going to be the same so he would have to lie, if he told the truth he would say no because the answer is not the same, and then u ask the second question who is the truthteller/who is not the truthteller
ceosir711 4 months ago
@ceosir711 You mean ... Q1 = Will your 2nd answer be the same as your 1st answer if I ask you the same question twice ? Suppose "E" is the truther, and you ask Q1 to "A" (who is a truth toggler) and he answers "NO", then you ask him, who is not the truthteller ? He answers "B, C & E are not truth tellers" - ( but he is lying ). If you ask him who the truther is , he can say " I am the truther ! " but he is lying, so your answer I think has a problem
EagleFeatherful 4 months ago
Nvm, I realized how the solution works now.
gunking1949 4 months ago
@EagleFeatherful Suppose you ask the first question to A, who is truthful toggler, he will answer with the correct truthteller, but you won't know if he is actually telling the truth or not, what do u do from there?
gunking1949 4 months ago
@gunking1949 suppose E is the truther and "A" answers "E" because "A" is a truthful toggler.
Now I ask "A" Q2 - " I know that between "B, C and D that they might all be togglers but nonetheless tell me of those 3, who 2 and only 2 togglers are ?" ( All 3 are togglers - right ? ) So "A" cannot answer BC, nor BD nor CD because he must lie - so he says something like : "none of those 3 are togglers ! " Now I know he told the truth about E - so E is the truther in this case.
EagleFeatherful 4 months ago
I challenge Istinnjj and Sal to find a flaw in my solution !
EagleFeatherful 5 months ago
My solution was to ask one person the same question twice : What is each person, a truthteller or a toggler?
If that person is a toggler, they will give me a different answer each time.
a = truthteller b = toggler
Ex: truth toggler says: bbbab then aaaba.
lie toggler says: aaaba then bbbab.
truthteller says: bbbab then bbbab.
So even if I happen to ask a toggler, I can still figure out who is the truth teller by seeing which person was the only one of their type in each answer.
Ribunculous 5 months ago
@Ribunculous
Your solution will not work. A truth toggler can say bbbab followed by bbbba as his answers. So who is the truther ? You dont know. When he lies, all he has to do is make one part of his answer a lie.
EagleFeatherful 5 months ago
@EagleFeatherful Glad to see a reply so soon! :o
So I can trust that they will lie, but I can't trust them to lie the way I want them to?
Ribunculous 5 months ago
@Ribunculous
Right. It seems to be agreed by most that the sky is the limit for a lying toggler.
If you asked him who the togglers are and he is lying , he could reply
" there are no togglers here at all ! " Take a peak at my solution. It works, and it allows for a lying toggler to be as creative as he likes with his lie.
EagleFeatherful 4 months ago
@Ribunculous Doesn't count. It's essentially asking 10 questions.
I mean, the first round of questions would really be enough, if done this way, because the second round would just give the 'mirrored' answer. (check your own post: first round, truth toggler says bbbab, truthteller says bbbab, liar says aaaba. You can just pick the odd one out.)
Lolznator 4 months ago
i got it !!!!!!" its the first one ive got with these videos and under 1min too. ,,
monegro3001 5 months ago
My solution is to ask a random guy who are liars. Supposing he is lying he would have to say only guy and that would answer everything. But if he picks 3 guys, then he is telling the truth, the only guy would therefore would be the tt.
paulyeo23 5 months ago
@paulyeo23 Suppose you ask person A ( and A is a toggler ) who are liars ?
If he is lying, he can tell you that persons A, C, D & E are all togglers.when in fact person E is a truther.( so he is lying - right ? ) so now what will you ask him ? If you ask him again he will tell you the truth this time . He will answer A, B, C and D which is truthful but then you will not know whetther B or E is a truther.
My answer is complete and it works. ( 4 part solution below )
EagleFeatherful 5 months ago
I answered it by asking the same person "Who is telling the truth?" twice in a row.
JustinPadovani 5 months ago
@JustinPadovani But then you don't know which one of the answers is the truth, unless you accidentally asked the truthteller (20% chance).
SonofOxford 5 months ago
Part 4, in my solution, I am proposing that when a toggler lies he can dream up any thing he likes, I pose no restriction, he can be as evasive as he can be, but the key is that if he told the truth the first time, he must find a way to lie to my second question
even if his answer sounds off base.
EagleFeatherful 5 months ago
Part 3 to my solution. But suppose he answers "E" the first time and he was telling the truth. (ie "E" is the truther) then I ask him my "B,C, D" question, and he must lie. Go ahead ! Come up with your best but it must be a lie. How about "none of those 3 are togglers !". I can now declare "E" to be the truther.
If however his answer to Q1 is "B" then in my second question. instead of asking about "BC & D" , I ask about "C, D and E", and likewise if he answers "C" or "D"
EagleFeatherful 5 months ago
Part 2 to my solution. If his answer to question 1 was "A - ME ! " then when I ask him the same question again, he must direct me to the truther, ( if he i a toggler, then he lied the first time - now he must be truthful)
But suppose he answers "E" the first time and he was lieing. (ie "D" is the truther) then I ask him my "B,C, D" question, and he will be truthful and answer "B & C" Now I can declare that "D" is the truther.
EagleFeatherful 5 months ago
Here is my solution. ( they are lined up left to right, "A" through "E")
I ask "A", who is the truther ? If he answers "A", then I ask him again
who is the truther ? Whatever his answer is, he will be directing me to the truther.
But if his answer to question 1 was for example "E", then I pose this second question also to "A" :: " I know that between "B, C and D that they might all be togglers but nonetheless tell me of those 3, who 2 and only 2 togglers are ?
EagleFeatherful 5 months ago