Puzzle: The Two Doors and the Two Doorkeepers: How to Get to Heaven?

A man who was was good to his neighbors but wasn’t a believer in God died and was standing before the Pearl Gate. Peter, who had the keys, according to this story, said to him: “Son, you have been good to your neighbors and so you are given an opportunity to find out your way into heaven. Remember you have only one chance.

1. There are two doors. One of them is a door to heaven and another is a door to hell.
2. In front of each door, there is a doorkeeper.
3. One of the doorkeepers always speaks the lie; the other always speaks the truth.
4. You have to ask only one question to either one of them, and decide which door you will enter through.

What question will he ask? Note: he doesn’t know which door leads to hell or to heaven and he also doesn’t know who is the liar and who is true.

If the answer is tooooo difficult, scroll down………………………


Answer:
He will ask to any one of them “What will the other doorkeeper say if I ask him the way to heaven?” and then enter into the opposite door.
1. If he goes to the liar and asks the question, the liar will tell a lie and show the false door; which means that he has to enter its opposite, the true one.
2. If he goes to the true one and asks the question, he will tell the truth and show the same false door that the liar is going to show; which means that he has to enter its opposite, the true one.

Advertisements

Puzzle: Men with Black and White Hats

There are four men (A-B-C-D) standing on each step of a stairs. There is a wall between C and D so that none can see D. Each is wearing either a black or white hat. Two of them wear black hats and two of them wear white hats. Actually, A is wearing white; B, black; C, white; and D, black.
Rules:
1. None of them must talk to each other.
2. None of them can look behind.
3. None can remove his hat.

Who will be the first one to tell the color of his hat?

If you have tried very hard and are still curious to find out, scroll down…..


Answer:
B will answer. Let’s check his reasoning.
1. If I was “C” I cannot know the color of my hat because I can neither see D nor can I look behind.
2. If I was “A” I could answer if I saw two black hats before me, I would know that I had white on; similarly, if I saw two white hats before me, then I would know that I had a black hat on. However, if I saw a black and a white hat, then I wouldn’t be able to know what color hat I wore because I couldn’t see D.
3. A is still silent, which means he sees a white and black hat.
4. I see a white hat before me on C.
5. Therefore, I am wearing a black hat.