This is a well-known logic puzzle in English: The Martian Rub
After his spaceship landed on Mars, astronaut Mark disembarked and approached the first Martian he saw.
"Am I headed for the geological dig?" he asked.
The Martian rubbed his stomach.
Astronaut Mark knew that Martians could understand some Earth-talk, but were not able to speak it; Mark, like so many Earthlings, could neither speak nor
understand Martian gestures. He didn't know whether rubbing the stomach meant yes or no. But by asking one additional question, Mark was able to find out.
What was that question?
Answer:After his spaceship landed on Mars, astronaut Mark disembarked and approached the first Martian he saw.
"Am I headed for the geological dig?" he asked.
The Martian rubbed his stomach.
Astronaut Mark knew that Martians could understand some Earth-talk, but were not able to speak it; Mark, like so many Earthlings, could neither speak nor
understand Martian gestures. He didn't know whether rubbing the stomach meant yes or no. But by asking one additional question, Mark was able to find out.
What was that question?
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| The Martian and Astronaut Mark |
Astronaut Mark rubbed his stomach and asked, "Did you do this?"
Whatever the Martian did in reply would mean yes.
