Two Computers
Riddle: Your in a room there is 2 doors 1 leads to instant death one lead to the way out. You don't know which is which but there are 2 computers 1 always lies 1 always tells the truth you don't know which is which. You get I sentence to ask 1 computer. What do you ask a computer to know 100% which door is safe to go through how do you know?
Answer: You ask one computer what the other computer would say if you asked it which door to go through. If you asked the truthful computer it would tell you what the lying computer would say if you asked th lying computer it would tell you the opposite of what the thmruthful computer would so either way go through the opposite door it says.
Source: https://www.riddles.com/5195
