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Escaping the dungeon (Posted on 2002-04-26) Difficulty: 2 of 5
You are trapped in a dungeon, and see two doors in front of you. One is a way out, andther will lead to certain death.

Two people are standing in front of these doors, one of them a Knight, another - a Liar. Naturally, you do not know who is who, but they know each other's true nature.

Both the people know which way is correct, but you can only ask one question of one of them before making your choice. What will you ask?

See The Solution Submitted by levik    
Rating: 3.0000 (18 votes)

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Solution Old one | Comment 14 of 20 |

You have to ask a question that involves both of them. You can either ask "If I ask your partner what is the door to freedom, What would he say?" or "If I ask your partner what is the door to death, What would he say?"

If you ask the first question to the knight, then the knight will answer that the liar will point you towards certain death. If you ask it to the liar, he will say that the knight will point you to certain death. They both say the same thing as both involve a liar on the answer, so you know that the answer is a lie. In simple terms, they will show you the door to certain death. Take the other door and your free to go do whatever you want.

If the ask the second question to the knight, he will say that the liar will point you to freedom. If you ask it to the liar, he will say that the knight will point you to freedom. You take the door that they mention.


  Posted by Paddy on 2005-12-23 04:23:18
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