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Difficult Riddle!

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^^cuz you're only allowed 4 questions to 4 people lol.

But there are 5 people in the room and we are allowed to ask one question to each!

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Fine if we can only ask 4 questions I can still do it.

Assuming my method of assertaining whether the first person is T or L to be correct.

Ask the second person if the correct door is one of D1, D2 or D3. If P1 is a liar then P2 is honest (and if P1 is honest then P2 is a liar) so depending on his answer ww will know if the door we want is one of those three or one of the other 2.

Now we either have 3 doors left to choose from or 2.

Assume we have 3 left (D1, D2 and D3). We can now use my method which could be used if we had 5 questions:

Ask the third person if D1 is the one we want, since we know if he is T or F we can either choose or eliminate this door.

Ask the fourth person if D2 is the one we want, since we know if he is T or F we can either choose or eliminate this door.

Now we have either gotten the right door or eliminated a further 2 doors, leaving the correct door! D3 in this case.

Done now?

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Fine if we can only ask 4 questions I can still do it.

Assuming my method of assertaining whether the first person is T or L to be correct.

Ask the second person if the correct door is one of D1, D2 or D3. If P1 is a liar then P2 is honest (and if P1 is honest then P2 is a liar) so depending on his answer ww will know if the door we want is one of those three or one of the other 2.

Now we either have 3 doors left to choose from or 2.

Assume we have 3 left (D1, D2 and D3). We can now use my method which could be used if we had 5 questions:

Ask the third person if D1 is the one we want, since we know if he is T or F we can either choose or eliminate this door.

Ask the fourth person if D2 is the one we want, since we know if he is T or F we can either choose or eliminate this door.

Now we have either gotten the right door or eliminated a further 2 doors, leaving the correct door! D3 in this case.

Done now?

I wonder whether there is any way out hihihih :D :D :D B) B) sounds cool

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Fine if we can only ask 4 questions I can still do it.

Assuming my method of assertaining whether the first person is T or L to be correct.

Ask the second person if the correct door is one of D1, D2 or D3. If P1 is a liar then P2 is honest (and if P1 is honest then P2 is a liar) so depending on his answer ww will know if the door we want is one of those three or one of the other 2.

Now we either have 3 doors left to choose from or 2.

Assume we have 3 left (D1, D2 and D3). We can now use my method which could be used if we had 5 questions:

Ask the third person if D1 is the one we want, since we know if he is T or F we can either choose or eliminate this door.

Ask the fourth person if D2 is the one we want, since we know if he is T or F we can either choose or eliminate this door.

Now we have either gotten the right door or eliminated a further 2 doors, leaving the correct door! D3 in this case.

Done now?

Done. Problem is solved!

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Done. Problem is solved!

Dag, I'm too late :D

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Here is another method:

For N = 1 to 4: ask person N, "will person N+1 say door N leads to Islam?"

N is the right door only if we receive "No" as an answer, you know why? Because:

1) If P(N) is truthful: then P(N+1), liar, will deny that D(N) (the right door) leads to safety so P(N) will tell us "No".

2) If P(N) is liar: then P(N+1), truthful, will confirm that D(N) (the right door) leads to safety so P(N) will lie and tell us "No".

If the answer is "No" in any of the four questions, then the corresponding door (N) leads to Islam. If no "No" response is received, then the remaining fifth door leads to Islam.

And Allah knows best.

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I'll go further with the riddle: there is a solution to the problem using only 3 questions!!

So, bro freedslave, sis Haqqul_Yaqeen, bro hkrespect, BelinQuest, llogical, LibertÃ© or any other member: Can you solve the problem using maximum 3 questions?

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mind's tired right now, maa shaa allaah. in shaa Allaah, then be back later to try and solve if others haven't blatantly answered it.

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:D

I couldn't solve it using 4 questions, you think I can solve it with 3? lol but LibertÃ© is good, he might. :D

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I'll go further with the riddle: there is a solution to the problem using only 3 questions!!

:D

Anyone else knows the answer to this new riddle?

Well I'm stumped Iraq11...I tried it out a few days before but I couldn't get it and now I'm totally out of ideas to solve this.... :D

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I'll go further with the riddle: there is a solution to the problem using only 3 questions!!

It's quite a hard problem, but I'm sure IF members can solve it!!!

Anyone to try?

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Akum

what about if i ask them what colour my shirt is then i will know who lies and who doesnt

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Assalamu Alaykum

Maybe, order them to confront the enemies of Islam. The truthful will follow you, but the hypocrites will find an excuse not to follow you.

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I'll go further with the riddle: there is a solution to the problem using only 3 questions!!

So, bro freedslave, sis Haqqul_Yaqeen, bro hkrespect, BelinQuest, llogical, LibertÃ© or any other member: Can you solve the problem using maximum 3 questions?

Can anyone solve the problem with maximum 3 questions?

he is lying

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What would the other person answer if I asked: "Are you a liar?"

If the first answers: No then that means the first person is truthful.

If the first answers: Yes then that means the first person is liar.

Then you can ask the next people which door is the safe one...

Assalaamu Alaikum Wr Br

To Liberte:

if the first answers No, then they could be telling the truth that they aren't a liar or they could be lying by saying that theya re not a liar...you get me??

and it is the same thing for if they answer yes they are a liar because the answer itself is being truthful to the question...as in yes they are a liar meaning that they just told you that he is so he told the truth...

it works bith ways...that question would have a tricky answer...get it??

Inshallah tell me if u dnt understand my thinking..

Salaams

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i guess the question ought to be"are you a munafiq"...a yes answer means the person is truthful and a no answer means the person is not truthful.(saying of umar razi allahu anhu,"a person who does not doubt him/her self to be a munafiq is truly a munafiq")..this will show who the truthful is/are....next just say out loud,"i wish i knew which door lead to Islam"...the muslim among the 5 will have no choice but to show the correct door(that is how Islam is by definition: a muslim knows that 'mashvara/consultation is an 'imaanaa'...so the muslim among the 5 will be forced for his/her own sake to show the way)....salaam.

Edited by abukhaleel

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Hmmm. OK I think I got it.

What I would do is ask the first person: "Would the NEXT person say that door number one is the one we want if I ask him that?" And whatever the answer I get , I simply reverse it.

Basically if the man says "YES" then I should consider it as "NO", and if it's a "NO" I should take it as "YES". Reason being that if the person I ask is truthful, he will think regarding the lie that the next person is going to tell me and truthfully tells me the liar's answer, which is something I want to go against (For example if door number one is safe, the truthful man knows the liar will say it's NOT safe, and he will say "No" to me, so if I reverse it then it is "Yes" which is correct since it is safe). If the person I am talking to is a liar, he will think about the truthful answer the next man will tell me, and then HE will lie about it when telling me, so again the correct answer is the opposite of what is being said (If the door is safe, the liar knows the truthful man will say it is safe, but because he is a liar he will say it is not safe, so if I reverse it then it is "Yes" which is correct again)

By this method I establish a correct answer every question. I just ask them one by one regarding different doors one by one, and will know whether that door is safe or not every time.

The only remaining obstacle here is that we get to ask four questions, and there are five doors. I think the answer to that lies in the fact that if after 4 questions I get three yeses and one no, the door that I was told about to be a "no" is the safe one that I should use (after reversing the answer), and I don't need to know any other door. If the four doors I ask about are all yeses, then in reality they are all "no", and therefore the only remaining door is the truly safe one.

Did I get it right? :sl:

Sam

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Oops, I just went through the messages on page two and realized the answer was already found. Ok, so now the challenge is three questions. Let's give this a try:

Ask person number 1: "If I ask the next person about doors 1, 2, and 3, if the safe door is amongst them, what would he say?" and again reverse the answer. If the man says yes, then I know it's a no and the door is either 4 or 5, if the man says no, then I know it's yes and that it's indeed one of those three.

There you go, now we have two questions left and maximum three doors left. Another question to the next person would be breaking down the current list of doors we know the door is in. If it was 4 or 5, we just ask like before about them individually and use the safe one. If it was indeed amongst 1, 2 and 3, then we ask about individual doors, and if we get two yeses, or in reverse would mean two "no", it means the third door left is the only left option.

How is that one?

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Oops, I just went through the messages on page two and realized the answer was already found. Ok, so now the challenge is three questions. Let's give this a try:

Ask person number 1: "If I ask the next person about doors 1, 2, and 3, if the safe door is amongst them, what would he say?" and again reverse the answer. If the man says yes, then I know it's a no and the door is either 4 or 5, if the man says no, then I know it's yes and that it's indeed one of those three.

There you go, now we have two questions left and maximum three doors left. Another question to the next person would be breaking down the current list of doors we know the door is in. If it was 4 or 5, we just ask like before about them individually and use the safe one. If it was indeed amongst 1, 2 and 3, then we ask about individual doors, and if we get two yeses, or in reverse would mean two "no", it means the third door left is the only left option.

How is that one?

Awesome !

That's the correct answer. Thank you.

Iraq11

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Even though it's been solved, very unique riddle!

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Salaam, I wonder how much time theyspend in making the Riddles in the first place. solving the Riddles using logic reals spins my brain around and still I cannot solve them.

Salaam.

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Although this was posted in 2006 i wanted to still have a go ... in page 2 it says they solved it, but i didnt understand the answer...

here's a way of doing it though:

1st Q: Ask person one: Is there any Muslims in any of the rooms.

if he is a Liar, he would say no

If he is truthful, he would say yes..

If he says yes, then you no that person:

1 is truthful,

2 is liar,

3 is truthful,

4 is liar

5 is truthful

2nd Q: point at door 1 and ask person 2 if that's the correct door [who you know is going to lie],

if he says no, then that is the correct door - and you solved the problem in 2 questions!

if he says yes, then door 1 can be totally ignored, which leads us to question 3 [and there are 4 possibilities now]:

3rd Q: ask person 3 [truthful] 'is the correct door in either door 2 or 3?'

if he says yes, then all you have to do is point at door 2 and ask the next person [liar] if its the correct one. if he says yes, then you know the right door is door 3. If he says no then its door 2... [so thats total of 4 Q's]

but if the truthful person says no, then you know that it is either door 4 or 5. now you can point at door 4 and ask the next person if its that one and....[same as above]

So in this method, you can get it in either 2 questions or 4. Also changing question 2, would allow you to get it in 3 questions and I can think of 2 different way altogther...but its gna be to long to type