Question

Tell me the answer

to You are walking down a road, seeking treasure. The road branches off into three paths. A guard stands in each path. You know that only one of the guards Is telling the truth, and the other two are lying. Here is what they say: • Guard 1 : The treasure lies down this path. • Guard 2: No treasure lies down this path, seek elsewhere. • Guard 3: The first guard is lying. Which path leads to the treasure?

Answer 1

Answer: Guard 2

Step-by-step explanation

Consider three cases A, B, and C where,

• A: Guard 1 tells the truth (the others lie)
• B: Guard 2 tells the truth (the others lie)
• C: Guard 3 tells the truth (the others lie)

In case A, the treasure is with guard 1. Guard 2's statement would be false, which means that the treasure is with guard 2. This is a contradiction. Therefore, case A isn't possible.

In case B, the treasure is not with guard 2. Guard 3 claims guard 1 is lying. But guard 3 is a liar in case B, which means guard 1 tells the truth. But this contradicts the fact we know guard 1 is lying in case B. The contradiction allows us to cross case B off the list. Case B isn't possible.

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The previous paragraphs allowed us to eliminate options A and B off the list.

The only thing left is case C.

In case C, guard 1 saying "The treasure lies down this path" is a lie (due to guard 3's assumed true statement; also due to how case C is set up). The treasure is with guard 2 or guard 3. Guard 2 saying "No treasure lies down this path, seek elsewhere" is also a lie, so it must be with guard 2. Luckily we don't run into any contradictions here.