Fierce_LiNk Posted June 6, 2011 Posted June 6, 2011 7. Easy peasy. You turn on one switch for about a minute. Then, you turn it off and turn another one on. Go into the room. The bulb that is currently lit corresponds to the switch that is currently on. Feel the bulbs that are off. One is warmer than the other. That corresponds to the switch that you turned on and then off again. The other bulb that is cold and off is the switch that you didn't touch.
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 2. Pascal's Rule Correct. 8. Michael Phelps and Mark Spitz. Correct. 7. Easy peasy. You turn on one switch for about a minute. Then, you turn it off and turn another one on. Go into the room. The bulb that is currently lit corresponds to the switch that is currently on. Feel the bulbs that are off. One is warmer than the other. That corresponds to the switch that you turned on and then off again. The other bulb that is cold and off is the switch that you didn't touch. Well done :p
Dannyboy-the-Dane Posted June 6, 2011 Posted June 6, 2011 4. Three thieves are arrested. They are each given t-shirts, and told to stand in a line, and D to stand behind a door: A B C | D. A can see B and C, B can see C, no one can see D. No one can see their own shirt. They are told there are two yellow shirts and two black shirts. If one of them can say the colour of his own shirt they can go free. How can this be accomplished, and by whom? (hint, they are all competent) I guess if B and C are wearing the same colour shirt, A will know his own shirt is the other colour? Though I'm not sure I get the point of the exercise, so I may be overlooking something ...
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 (edited) 9. Matriarchy? Incorrect. Matriarchy refers to social structure and culture, rather than government. I guess if B and C are wearing the same colour shirt, A will know his own shirt is the other colour? Though I'm not sure I get the point of the exercise, so I may be overlooking something ... Sorry I wrote three thieves instead of four The point is that knowing there are two yellow shirts and two black ones, with this set-up at least one should be able to tell their own shirt colour without looking. Edited June 6, 2011 by heroicjanitor
Dannyboy-the-Dane Posted June 6, 2011 Posted June 6, 2011 Incorrect. Sorry I wrote three thieves instead of four The point is that knowing there are two yellow shirts and two black ones, with this set-up at least one should be able to tell their own shirt colour without looking. So my explanation was correct?
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 So my explanation was correct? No it wasn't because you only solved for one case.
Dannyboy-the-Dane Posted June 6, 2011 Posted June 6, 2011 No it wasn't because you only solved for one case. So let me get this straight: Four thieves are arrested and lined up in a row, all facing the same way. The fourth thief in the row, D, is separated from the others by a door. They are given t-shirts, two yellow, two black, and they can only see the t-shirts of those in front of them. No one can see D. If either of them can identify his own shirt colour, they all go free?
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 So let me get this straight: Four thieves are arrested and lined up in a row, all facing the same way. The fourth thief in the row, D, is separated from the others by a door. They are given t-shirts, two yellow, two black, and they can only see the t-shirts of those in front of them. No one can see D. If either of them can identify his own shirt colour, they all go free? Exactly, if any of them can state the colour of their t-shirt without looking at it(perhaps headband would be better)
Zell Posted June 6, 2011 Posted June 6, 2011 4. B can always know what colour shirt he is wearing. Let's say B and C are wearing the same colour. Then A would deduce the colour of his own shirt (because it would be the other colour to what B and C were wearing). A, having figured out what colour shirt he is wearing, can then shout to the rest that he has figured out his shirt colour. B would then deduce that the colour of his shirt is the same as C. If B and C are wearing different colours, then A won't be able to figure out his own colour. So A would remain silent. Then B would deduce that him and C are wearing different colours, and so he would know that he is wearing black if C is wearing yellow and yellow if C is wearing black. Long story short, A will know if B and C are wearing the same colour and B will know if B and C are wearing different colours.
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 4. B can always know what colour shirt he is wearing. Let's say B and C are wearing the same colour. Then A would deduce the colour of his own shirt (because it would be the other colour to what B and C were wearing). A, having figured out what colour shirt he is wearing, can then shout to the rest that he has figured out his shirt colour. B would then deduce that the colour of his shirt is the same as C. If B and C are wearing different colours, then A won't be able to figure out his own colour. So A would remain silent. Then B would deduce that him and C are wearing different colours, and so he would know that he is wearing black if C is wearing yellow and yellow if C is wearing black. Long story short, A will know if B and C are wearing the same colour and B will know if B and C are wearing different colours. Correct
gmac Posted June 6, 2011 Posted June 6, 2011 1. The Curious Incident of the Dog in the Night Time and the fictional Detective is Sherlock Holmes
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 1. The Curious Incident of the Dog in the Night Time and the fictional Detective is Sherlock Holmes Correct, perfect answer. I thought Danny would go for this one, given that he is in fact the detective in question :p
Diageo Posted June 6, 2011 Posted June 6, 2011 5. Silly string can be used to detect trip-wires without setting them off.
Dannyboy-the-Dane Posted June 6, 2011 Posted June 6, 2011 4. B can always know what colour shirt he is wearing. Let's say B and C are wearing the same colour. Then A would deduce the colour of his own shirt (because it would be the other colour to what B and C were wearing). A, having figured out what colour shirt he is wearing, can then shout to the rest that he has figured out his shirt colour. B would then deduce that the colour of his shirt is the same as C. If B and C are wearing different colours, then A won't be able to figure out his own colour. So A would remain silent. Then B would deduce that him and C are wearing different colours, and so he would know that he is wearing black if C is wearing yellow and yellow if C is wearing black. Long story short, A will know if B and C are wearing the same colour and B will know if B and C are wearing different colours. Ah, of course, I didn't consider the fact that they could just talk to each other! :p It's funny how simple logic is sometimes thrown out the window when focusing on constructed cases. But why mention that they're thieves, though? It's irrelevant to the case. Correct, perfect answer. I thought Danny would go for this one, given that he is in fact the detective in question :p Heh, I've only read the four novels. I haven't started on the short stories yet.
Jonnas Posted June 6, 2011 Posted June 6, 2011 Ah, of course, I didn't consider the fact that they could just talk to each other! :p It's funny how simple logic is sometimes thrown out the window when focusing on constructed cases. But why mention that they're thieves, though? It's irrelevant to the case. They are all prisoners submitted to a test in the original riddle. Many similar riddles use prisoners as test subjects. 9. Hell Gynecocracy
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 Ah, of course, I didn't consider the fact that they could just talk to each other! :p It's funny how simple logic is sometimes thrown out the window when focusing on constructed cases. They can't talk to each other, it would make it pointless. B infers from A's silence that his hat and C's hat must be different colours. He can see C's hat, and thus picks the opposite. It's why the hint was that they were competent, and A isn't silent because he is thick or something :p But why mention that they're thieves, though? It's irrelevant to the case. It is irrelevant, but we know that from the answer :p It was mainly to contrive a situation where they were captured and had to try to win freedom.
Dannyboy-the-Dane Posted June 6, 2011 Posted June 6, 2011 They are all prisoners submitted to a test in the original riddle. Many similar riddles use prisoners as test subjects. Well, yeah, but it's still irrelevant to the test, so essentially it's pointless to mention it.
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 5. Silly string can be used to detect trip-wires without setting them off. Correct 9. Hell Gynecocracy I also would have accepted gynocracy(had to google your one :p )
Dannyboy-the-Dane Posted June 6, 2011 Posted June 6, 2011 They can't talk to each other, it would make it pointless. B infers from A's silence that his hat and C's hat must be different colours. He can see C's hat, and thus picks the opposite. It's why the hint was that they were competent, and A isn't silent because he is thick or something :p It is irrelevant, but we know that from the answer :p It was mainly to contrive a situation where they were captured and had to try to win freedom. Well, no, them being able to talk to each other was bad wording on my part. But it's not A being thick; it's logical that he will state his shirt colour if he figures it out, because the test would then be over, and B knows this, making it possible for him to figure his shirt colour out if A doesn't say anything. But in a thought experiment with such contrived parameters, why bother coming up with a plausible situation?
heroicjanitor Posted June 6, 2011 Posted June 6, 2011 Well you have to gather all of the information you have, what does A see, what does C see etc. If you got that A would know if the two in front wore the same shirt, it wasn't much of a stretch to get the rest(that B would know that A would know if he and the guy in front had the same colour shirts). It's an induction type problem. If I make another quiz I'll do a murder mystery :p Or something less contrived.
Dannyboy-the-Dane Posted June 6, 2011 Posted June 6, 2011 Well you have to gather all of the information you have, what does A see, what does C see etc. If you got that A would know if the two in front wore the same shirt, it wasn't much of a stretch to get the rest(that B would know that A would know if he and the guy in front had the same colour shirts). It's an induction type problem. If I make another quiz I'll do a murder mystery :p Or something less contrived. Oh, there's nothing wrong with the case itself. Such thought problems often do have contrived or downright arbitrary parameters. And that's exactly why it bugs me that it's mentioned that they're thieves, since the mention of it suggests that it's a parameter as well, when it is in fact completely irrelevant. :p (Don't worry, it's just my perfectionism kicking in. )
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