A man left home running. He ran a ways and then turned left, ran the same distance and turned left again, ran the same distance and turned left again. When he got home there were two masked men. Who were they?
A light-tight wooden box has three switches on the outside that control three light bulbs on the inside. When the box is closed you can turn the switches on or off but when you open the box how can you tell which switch controls each bulb without touching the switches?