Who is the liar in this logic puzzle?

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    Logic Puzzle
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The logic puzzle involves three individuals at a philosophy party, where one claims the first person said he was a liar, and the third accuses the second of lying. Analyzing the statements reveals that the second person must be lying because a truth-teller would never admit to being a liar. Consequently, the third person, who calls out the second's lie, is a truth-teller. This conclusion highlights the intricacies of identifying truth and deception in logical scenarios. The discussion also touches on similar puzzles, emphasizing the appeal of logic-based reasoning.
  • #121
marqq said:
whatever you want...you have a 33% chance to find the prize...you pick #1...and you find that the door #3 is a fake...Your chances increase to 50%...so either you take #2 or you rest on #1 you heave the same chances to win the prise :)
no I don't think that is correct. its close, but not right. What if there are a million doors and after you choose Monty Hall/Bob Barker throws out 999998 of the bad doors and says it's either the one you chose or this one? do you think it is still a 50/50 chance then?
 
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  • #122
tribdog if there were 1milion doors you would have 1/1000000 chances to win the prise...if we-ll take off a fake one, either you change or you keep your door, you'll have a 1/999999 chances to win the prize...so...the answer is the same...you can do whatever you like...you have the same chances
 
  • #123
leto ... let me give you a hint...try to use the 1st weigh...make 2 options: 1.what if it tippes ao a 1st side, and 2.what if it tippes on second side... You'll have to work longer, but you have a lot more chances to find the odd ball :biggrin:
 
  • #124
I disagree. By removing the 999998 doors, the chance of the door you didn't pick being the door increases. The door you did pick could not be removed, and is therefore less likely to be the prized door.
 
  • #125
There are three possibilities with the first weigh. Either it tips to the left, right or stays level. I accounted for all three of these.

Edit:

I think you are assuming I label them l1-l4 and h1 - h4 because I assume I know this. I only label them as such so that I know later that, if one of them is the odd ball, they have to follow that pattern. A ball that was on the heavy side will never be the lighter odd ball.
 
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  • #126
leto said:
I disagree. By removing the 999998 doors, the chance of the door you didn't pick being the door increases. The door you did pick could not be removed, and is therefore less likely to be the prized door.

correct. in the million door scenario the chances of the door you picked being the correct door is 1 in a million, therefore wouldn't the chance of the other door being the correct one be 999999 in a million? The point being it is always better odds to make the switch in a situation like this.
another way of looking at it is this: after you make your first choice you are given the option of keeping your door or taking all 999999 of the other doors.(which is the same thing as taking one door that may be right and throwing out 999998 wrong ones) Do you keep your 1 or take all 999999 of the others?
 
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  • #127
leto said:
I disagree. By removing the 999998 doors, the chance of the door you didn't pick being the door increases. The door you did pick could not be removed, and is therefore less likely to be the prized door.
The problem allow us to eliminate only one door...From 3 doors or from 100000000 doors...we are able to remove only one door...
I'll reed about probabilyties and i'll give you an answer
 
  • #128
leto said:
There are three possibilities with the first weigh. Either it tips to the left, right or stays level. I accounted for all three of these.

Edit:

I think you are assuming I label them l1-l4 and h1 - h4 because I assume I know this. I only label them as such so that I know later that, if one of them is the odd ball, they have to follow that pattern. A ball that was on the heavy side will never be the lighter odd ball.
sorry ... i missunderstood your "l-f" definition...i was tired and i thought you ment left-right...and swiching the balls, an left becomes right and viceversa...therefore i missjudged your solution...i am deeply sorry...your answer is as corect as it can be... I'm really sorry about that
 
  • #129
Another one..A funny one

The mother is 21 years older than the son.In 6 years, the son will be 5 times younger then his mother.Question: where is the father now? :rolleyes:
 
  • #130
enjoying himself :)
 
  • #131
pig said:
enjoying himself :)
you are closer to the answer than you imagine :biggrin:
 
  • #132
marqq said:
you are closer to the answer than you imagine :biggrin:

i got the answer, that's why i wrote that ;)
 
  • #133
would you please enlarge your answer for the others? :wink:
 
  • #134
Here's an easy one. See if you can solve this riddle in under 30 seconds...

Two Russians are walking down a street. One Russian is the father of the other Russian's son. How are they related?
 
  • #135
Husband and wife? In second thought, I don't know how things work in Russia so my answer would be "they had sex".
 
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  • #136
tribdog said:
no I don't think that is correct. its close, but not right. What if there are a million doors and after you choose Monty Hall/Bob Barker throws out 999998 of the bad doors and says it's either the one you chose or this one? do you think it is still a 50/50 chance then?
Ahh yes, why not? Because Bob says "it is either the one you chose or the other", which implies that one of the doors is the right one. He does not ask "would you like to change your pick now", which doesn't necessarily mean one of the doors is the right one. So yes, your chances would be 50/50.
 
  • #137
Another funny one

We have a driver who has to make the distance between A and B in his own car...He drives the 1st 3rd of the distance with 40 km/h (he was reall calm) then he becomes angry and drives the 2nd 3rd with 120 km/h...then it calms down and asks himself what is the speed that he should use for haveing a decent average of 90 km/h

I'll ask you to try (before starting to calculate) an aproximation by intuition, and then make the difference to see it it was a small or a huge error :-p
 
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  • #138
Is 120 km/sec a typo or did you really mean that? If it's a typo he should drive at 110 km/h, if it's not... I don't think he can reach an average of 90 km/h after driving at ~400,000 km/h.
 
  • #139
If it's a typo he should drive at 110 km/h, if it's not...
sorry
I was thinkin at smth else
120 km/h
And about the 110km/h you are wrong :biggrin: !Hint : make an ecuation
 
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  • #140
I did...

90 = \frac{40 + 120 + x}{3}

x = 110

:confused:
 
  • #141
1/90 = 3(1/40 + 1/120 + 1/x)
 
  • #142
You do realize, marqq, that the solution to that equation is negative?
 
  • #143
is not negative...is just the infinite x
 
  • #144
marqq said:
would you please enlarge your answer for the others? :wink:

He is located inside the wife, at least a certain part of him.. I didn't want to spoil since it's simple but funny :)

As for the driver.. If t is time in which he would have to make the whole trip for his average to be 90 km/h, he spent exactly t on the first two thirds of the trip. Which means he would have to make the remaining 1/3 in 0 hours, going infinitely fast :)
 
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  • #145
pig said:
He is located inside the wife, at least a certain part of him.. I didn't want to spoil since it's simple but funny :)

As for the driver.. If t is time in which he would have to make the whole trip for his average to be 90 km/h, he spent exactly t on the first two thirds of the trip. Which means he would have to make the remaining 1/3 in 0 hours, going infinitely fast :)
Well done Pig :smile:
 
  • #146
i'm inside of an imaginary cyrcle on which a shark swims inteligently (he can change the direction or he may stop but he can't enter the cyrcle) 4times faster then i do. Can I exit the cyrcle without been cought by the shark?
:eek:
 
  • #147
Btw ...who-s the phorum administrator? i have a problem with my avatar and my signature :)
 
  • #148
Damn those true or false questions!

True or false, what is your name?
 
  • #149
off topic. erase your post :)
 
  • #150
Cannibals & Missionaries

Taken Hurkyl's legend:
l l=river < >=canoe C=Cannibals M=Missionaries

CCC MMM < > l l
C MMM l<C C>l < > CC
C MMM l< C > l C
CC MMM < > l l C
MMM l<C C>l C
MMM l l < > CCC
MMM l< C > l CC
C MMM < > l l CC
C M l<MM>l CC
C M l l < > CC MM
C M l<CM>l C M
CC MM < > l l C M
CC l<MM>l C M
CC l l < > C MMM
CC l< C >l MMM
CCC < > l l MMM
C l<C C>l MMM
C l l < > CC MMM
C l< C >l C MMM
CC < > l l C MMM
l<C C>l C MMM
l l < > CCC MMM
 

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