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Four liars


Best Answer TimeSpaceLightForce, 05 May 2013 - 03:36 PM

Spoiler for what i find
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#11 TimeSpaceLightForce

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Posted 30 April 2013 - 09:05 PM

Spoiler for

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#12 bonanova

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Posted 30 April 2013 - 09:23 PM

You meet four quadruplets at a party with a unique character flaw: they are all liars. When answering questions, the youngest of them lies every other time. The second youngest lies twice for every three questions. The next oldest lies three times for every four questions. And the oldest lies four times for every five questions. Each person must maintain their rate of telling lies but does not have to tell them in a pattern....eg. The oldest must tell four lies and one truthful answer for every five questions, so if asked five questions they may respond with lie, lie, true, lie, lie..then when asked another five questions they may respond with true, lie, lie, lie, lie. What is the minimum amount of questions needed to work out the order of birth for the quadruplets if you can't repeat questions or ask the same person a question consecutively?


So the 4/5 liar could not respond like this? TLLLL LLLLT ..... .....
That is, he could never lie on 5 consequetive responses?
That makes it much easier.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
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#13 BMAD

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Posted 01 May 2013 - 12:07 AM

 

You meet four quadruplets at a party with a unique character flaw: they are all liars. When answering questions, the youngest of them lies every other time. The second youngest lies twice for every three questions. The next oldest lies three times for every four questions. And the oldest lies four times for every five questions. Each person must maintain their rate of telling lies but does not have to tell them in a pattern....eg. The oldest must tell four lies and one truthful answer for every five questions, so if asked five questions they may respond with lie, lie, true, lie, lie..then when asked another five questions they may respond with true, lie, lie, lie, lie. What is the minimum amount of questions needed to work out the order of birth for the quadruplets if you can't repeat questions or ask the same person a question consecutively?


So the 4/5 liar could not respond like this? TLLLL LLLLT ..... .....
That is, he could never lie on 5 consequetive responses?
That makes it much easier.

 

He could.  What is meant in the op is that for every set of five questions the 4/5 liar will lie four times (with 4 lies at the end possibly).  if asked another set of five questions the liar will again lie four out of five times (with 4 lies at the beginning this time).  So:

 

if asked 5 questions

T L L L L (possibly)

next 5 questions

L L L L T (possibly)

so T L L L L L L L L T = 8L / 10total which reduces to 4/5


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#14 bonanova

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Posted 01 May 2013 - 10:05 AM

 

 

You meet four quadruplets at a party with a unique character flaw: they are all liars. When answering questions, the youngest of them lies every other time. The second youngest lies twice for every three questions. The next oldest lies three times for every four questions. And the oldest lies four times for every five questions. Each person must maintain their rate of telling lies but does not have to tell them in a pattern....eg. The oldest must tell four lies and one truthful answer for every five questions, so if asked five questions they may respond with lie, lie, true, lie, lie..then when asked another five questions they may respond with true, lie, lie, lie, lie. What is the minimum amount of questions needed to work out the order of birth for the quadruplets if you can't repeat questions or ask the same person a question consecutively?


So the 4/5 liar could not respond like this? TLLLL LLLLT ..... .....
That is, he could never lie on 5 consequetive responses?
That makes it much easier.

 

He could.  What is meant in the op is that for every set of five questions the 4/5 liar will lie four times (with 4 lies at the end possibly).  if asked another set of five questions the liar will again lie four out of five times (with 4 lies at the beginning this time).  So:

 

if asked 5 questions

T L L L L (possibly)

next 5 questions

L L L L T (possibly)

so T L L L L L L L L T = 8L / 10total which reduces to 4/5

 

So it's four lies for question 1-5. Four more lies for questions 6-10 and so forth.

Not quite what the OP says.

 

If it were four lies for every "five" questions then the lies, after the first truth,

would always come in groups of exactly four. It could not be T LLLLL LLLT

because questions 2-6 comprise "five" questions that do not contain a truth.

 

OK now it's hard again.


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#15 TimeSpaceLightForce

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Posted 02 May 2013 - 05:20 AM

Spoiler for

 

..but i think the askings is not limited so the solution is lower


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#16 BMAD

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Posted 05 May 2013 - 12:59 AM

Would it be easier to find the 1:1 lie:truth teller or the 4:1 lie:truth teller?


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#17 BMAD

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Posted 05 May 2013 - 02:47 AM

Spoiler for what i find

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#18 TimeSpaceLightForce

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Posted 05 May 2013 - 03:36 PM   Best Answer

Spoiler for what i find

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