quote:Originally posted by Flaming Toad on a Stick: Solid!
An electric train is moving north at 50 km/hr. It goes through a semicircular curve of radius 60 m. It enters the semicircle at 50 km/hr at time t=0 and maintains a constant tangental velocity. A constand wind velocity of 20 km/hr to the east is present at all times. At time t=.5s, find the direction in which the train's smokestack will blow.
posted
If you put a chair under someone, they're forced to sit down, thus lowering them. If you put the word chair in front of the word man, you've got chairman, which is an elevation from just man. "Giving someone the chair" is a euphemism for executing them in the electric (boogie woogie woogie) chair.
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Incidentally, I made that one up on the spot, so it may not be all that polished, but I'm happy with it.
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You are traveling and come to a fork in the road and are not sure which way to go. Identical twin brothers who you know show up, but you can't tell which one is which. One always lies and the other always tells the truth.
What one question can you ask them that will tell you which way to go?
Posts: 555 | Registered: Jun 2005
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quote:There is a game that has this sort of thing in it. Anybody know the name?
Mindtrap. Everytime threads like this come up I wish I owned the game. Maybe I'll look for it this weekend.
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quote:Originally posted by SC Carver: You are traveling and come to a fork in the road and are not sure which way to go. Identical twin brothers who you know show up, but you can't tell which one is which. One always lies and the other always tells the truth.
What one question can you ask them that will tell you which way to go?
Reminds me of a recent Bizarro cartoon, where you come across three people: one who always tells the truth, one who always lies, and one who kills anyone asking tricky questions.
Posts: 3486 | Registered: Sep 2002
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quote:Originally posted by SC Carver: You are traveling and come to a fork in the road and are not sure which way to go. Identical twin brothers who you know show up, but you can't tell which one is which. One always lies and the other always tells the truth.
What one question can you ask them that will tell you which way to go?
"Where would you point if I asked you which direction I should go."
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If it is the truthful brother he will point you in the right direction, if it is the lying one he will point you in the wrong way. You can't tell who is who.
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quote:Originally posted by SC Carver: You are traveling and come to a fork in the road and are not sure which way to go. Identical twin brothers who you know show up, but you can't tell which one is which. One always lies and the other always tells the truth.
What one question can you ask them that will tell you which way to go?
"Where would your brother point if I asked him which direction I should go." The answer will be the "wrong" way to go.
If you ask the truthful one where he would tell you to go, he will tell you the truth and show you the actual path he would tell you to go on, aka the right path.
If you ask the liar, he will lie about which path he would tell you to take (the wrong path) and instead tell you the other one, so he would point you to the right path.
They'd both point you to the right path with FToaS question.
Posts: 10177 | Registered: Apr 2001
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quote:Originally posted by MrSquicky: Flaming Toad got it as well.
If you ask the truthful one where he would tell you to go, he will tell you the truth and show you the actual path he would tell you to go on, aka the right path.
If you ask the liar, he will lie about which path he would tell you to take (the wrong path) and instead tell you the other one, so he would point you to the right path.
They'd both point you to the right path with FToaS question.
From a "shallow" logical stand, you are correct, FToaS’ question could do the trick, as NOT(NOT(A)) = A.
The “problem” with this version is that we have the same kind of paradox as in “I always lie”, which is a sentence that can’t be evaluated logically as “true” or “false”. So if we ask the lying brother about his own answer, his answer can’t be evaluated at all, as he can’t evaluate his “original” answer, thus not being able to lie about it. (Meaning that if he evaluates his first “false” as “true”, lying about it would give the “false” answer, contrary to your expectations)
This doesn’t happen when asking about his brother’s answer, since he knows that his brother would tell the truth (no problem in evaluating it), so lying about it is “straight forward”
quote:Originally posted by SC Carver: You are traveling and come to a fork in the road and are not sure which way to go. Identical twin brothers who you know show up, but you can't tell which one is which. One always lies and the other always tells the truth.
What one question can you ask them that will tell you which way to go?
"Which way would your brother tell me to go?"
Posts: 12266 | Registered: Jul 2005
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quote:Originally posted by BlackBlade: We organize into families, we wear black suits when we join.
Get in our way and we'll beat you, if your weaker then us we'll eat you.
The Mafia?
Fraid not, the Mafia do not eat people. I posted additional hints at the higher end of this page, it makes the Mafia even more out of the question.
Posts: 14316 | Registered: Jul 2005
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quote:Originally posted by suminonA: The “problem” with this version is that we have the same kind of paradox as in “I always lie”, which is a sentence that can’t be evaluated logically as “true” or “false”. So if we ask the lying brother about his own answer, his answer can’t be evaluated at all, as he can’t evaluate his “original” answer, thus not being able to lie about it. (Meaning that if he evaluates his first “false” as “true”, lying about it would give the “false” answer, contrary to your expectations)
The fact that he always lies to others doesn't necessarily means he always lies to himself. It doesn't mean he regognizes "false" as "true". I'm of the opinion that he could evaluate his answer perfectly. He obviously knows the difference between true and false, and chooses to give the false answer. If this weren't true, wouldn't your scenario be flawed as well? The lying brother needs to know how to evaluate true and false to know that his brother would point the right way.
Posts: 1594 | Registered: Apr 2006
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quote:Originally posted by vonk: I couldn't get this one when I heard it, so lets try it here:
Two fathers & two sons went into a bar to have a Friday night drink together. They spent $15. Each spent the same amount. How much did each man spend?
$3.75 each, making exactly $15? I am sure I got it wrong as thats absurdly easy.
$7.50 each. There were two men. Each was a father and a son.
There were *three* men, a grandfather, a father, and a son. Two fathers, and two sons. They each spent $5.
Posts: 4089 | Registered: Apr 2003
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quote: Reminds me of a recent Bizarro cartoon, where you come across three people: one who always tells the truth, one who always lies, and one who kills anyone asking tricky questions.
That wasn't in Bizarro. Or, if it was, then somebody is copying somebody.
quote: Reminds me of a recent Bizarro cartoon, where you come across three people: one who always tells the truth, one who always lies, and one who kills anyone asking tricky questions.
That wasn't in Bizarro. Or, if it was, then somebody is copying somebody.
quote:Originally posted by SC Carver: You are traveling and come to a fork in the road and are not sure which way to go. Identical twin brothers who you know show up, but you can't tell which one is which. One always lies and the other always tells the truth.
What one question can you ask them that will tell you which way to go?
"Which way would the other brother tell me to go?"
(ugh, that'll teach me to finish reading a thread first...)
Posts: 4515 | Registered: Jul 2004
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quote:Originally posted by SC Carver: You are traveling and come to a fork in the road and are not sure which way to go. Identical twin brothers who you know show up, but you can't tell which one is which. One always lies and the other always tells the truth.
What one question can you ask them that will tell you which way to go?
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