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Life or death
By Thomas Coton on Monday, October 07, 2002 - 07:39 pm:

You are in front of two doors. One of them leads to life, the other death. They are guarded by two brothers, one of whom always lies, and one of whom is always truthful. You do not know which is which. You may ask one question to one of the brothers. What is it?

P.S. My personal answer, "Tell me which one leads to life, and no messing around cause you're going through first" is not accepted.

P.P.S. I know the answer!

By Ngoc Tran on Tuesday, October 08, 2002 - 08:45 am:

Here is the question:

"Could you please tell me which way your brother would tell me to lead to life?"

If that's the true one --> he would point to the Dead door.

If that's the liar --> he would point to the Dead door.

In both case - they would point to the dead door --> just take the other way.

By Yatir Halevi on Tuesday, October 08, 2002 - 09:47 am:

That is if each of the brothers know that the other always lies or always tells the truth.

Yatir