Challenge 2
-
Since we are doing math puzzles, consider the following: You are one of three prisoners in a jail. The King has picked one prisoner at random to be executed at dawn. The jailer knows the King, and has learned the true identity of the person to be executed. The jailer comes in, takes you asside and says: "See that guy over there? It's not him" Given this statement, what are your odds of being executed at dawn? You should assume that there are no word tricks here and what the jailor said is true. Clearly the answer is either 33% or 50%. Which is it? Ed Dixon
-
Since we are doing math puzzles, consider the following: You are one of three prisoners in a jail. The King has picked one prisoner at random to be executed at dawn. The jailer knows the King, and has learned the true identity of the person to be executed. The jailer comes in, takes you asside and says: "See that guy over there? It's not him" Given this statement, what are your odds of being executed at dawn? You should assume that there are no word tricks here and what the jailor said is true. Clearly the answer is either 33% or 50%. Which is it? Ed Dixon
50% - it's either you or the 3rd guy. --Mike-- http://home.inreach.com/mdunn/ This must be Thursday. I never could get the hang of Thursdays...
-
Since we are doing math puzzles, consider the following: You are one of three prisoners in a jail. The King has picked one prisoner at random to be executed at dawn. The jailer knows the King, and has learned the true identity of the person to be executed. The jailer comes in, takes you asside and says: "See that guy over there? It's not him" Given this statement, what are your odds of being executed at dawn? You should assume that there are no word tricks here and what the jailor said is true. Clearly the answer is either 33% or 50%. Which is it? Ed Dixon
In a Logic Puzzle such is this what is important is what effects You and not the others so to Speak. Remember the Jailer knows; Assuming you are prisoner A, The Jailer points to prisoner B; (And says its not him ) So you know it is prison C or yourself. Thus there is a 50% chance it is you, But Why did the jailer Talk to You and not to Prisoner C ? Because if he had talked to prisoner C it would have been impossible for him to make the Statement ! Also if the jailer had spoken to Prisoner C; He could have made the statement and it would be a 50% chance he had used you and not the other prisoner ! But he didn't so you just lost 50% Thus it Is in fact 100 % chance it is you, Weird but True Regardz Colin :cool:
-
In a Logic Puzzle such is this what is important is what effects You and not the others so to Speak. Remember the Jailer knows; Assuming you are prisoner A, The Jailer points to prisoner B; (And says its not him ) So you know it is prison C or yourself. Thus there is a 50% chance it is you, But Why did the jailer Talk to You and not to Prisoner C ? Because if he had talked to prisoner C it would have been impossible for him to make the Statement ! Also if the jailer had spoken to Prisoner C; He could have made the statement and it would be a 50% chance he had used you and not the other prisoner ! But he didn't so you just lost 50% Thus it Is in fact 100 % chance it is you, Weird but True Regardz Colin :cool:
Colin, you were on the right track, but you can not add percentages as simple as that. The correct answer is 66% - your arguments show that you have 2 to 1 chance over prisoner C. There is similar situation in bridge (card game) where it is called limited choice. If you want I can show you an example.
-
Colin, you were on the right track, but you can not add percentages as simple as that. The correct answer is 66% - your arguments show that you have 2 to 1 chance over prisoner C. There is similar situation in bridge (card game) where it is called limited choice. If you want I can show you an example.
Nedad, You are correct, Regardz Colin Davies
-
Since we are doing math puzzles, consider the following: You are one of three prisoners in a jail. The King has picked one prisoner at random to be executed at dawn. The jailer knows the King, and has learned the true identity of the person to be executed. The jailer comes in, takes you asside and says: "See that guy over there? It's not him" Given this statement, what are your odds of being executed at dawn? You should assume that there are no word tricks here and what the jailor said is true. Clearly the answer is either 33% or 50%. Which is it? Ed Dixon
The correct answer to the puzzle is 1/3. You can arrive at this answer with conditional probablilty, or by reason. The jailer knows the identity of the person selected. As a result he can always come to you and point to one of the others and say "See that guy over there? It's not him". In fact, he can go to each of the prisoners and do this. Thus he effectivly given you no new information. You already knew that one of the other two was not the one, and he just told you which one. Suppose you do the experiment 300 times. On average you would expect to be chosen 100 times, and the above would occur every time. Ed Dixon
-
The correct answer to the puzzle is 1/3. You can arrive at this answer with conditional probablilty, or by reason. The jailer knows the identity of the person selected. As a result he can always come to you and point to one of the others and say "See that guy over there? It's not him". In fact, he can go to each of the prisoners and do this. Thus he effectivly given you no new information. You already knew that one of the other two was not the one, and he just told you which one. Suppose you do the experiment 300 times. On average you would expect to be chosen 100 times, and the above would occur every time. Ed Dixon
BUT.... if the jailer had come to you and (honestly) said, "it's not you", then your chances would be 0%. The fact that he's eliminating one of the other guys means that there's only one of two possibilities left: 50%. So the jailer has indeed given you new information: it's either you or one more other guy (50%), whereas before that you thought it was you or one of the two other guys (33%). So, from "your" standpoint, the jailer's information just increased your changes of dying to 50%. Think about it, wouldn't you feel the same if this happened to you? Of course, there's also the issue of trust. If you don't trust the jailer (which I probably wouldn't), then your changes continue being 33%. Regards, Alvaro