Elon Musk dishing out riddles during job interviews is what you'd kind of expect.
Of course, he's not asking your bog-standard conundrum 'What's black and white and read all over?' - OK typing 'read' out is a dead giveaway - instead, the SpaceX owner reportedly name-drops a planet, albeit it is Earth, and has left people completely baffled.
Elon Musk's 'favorite' riddle
If you're an engineer hoping to work at the billionaire's rocket company you may be asked the following riddle: "You’re standing on the surface of the Earth. You walk one mile south, one mile west and one mile north. You end up exactly where you started. Where are you?"
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Before giving you the most common answer we'll fire off some 'wrong answers', which could technically be right if you move the goalposts.
Presh Talwalkar, owner of YouTube channel MindYourDecisions, uploaded a video explaining how to solve the bizarre question.
He wrote in the caption: "This puzzle is a classic brain teaser that was asked at Microsoft. It is also one of the favorites of Elon Musk, co-founder of PayPal and Tesla Motors."
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In the comments, people got a little bit creative - which I'm sure the world's richest man would probably appreciate... I think?
"My answer: In debt," one user typed.
"If you're in debt, and you walk 1 mile South, 1 mile West, and 1 mile North, you're still in debt."
While another wrote: "Suppose I go to the effort of adopting three dogs, and naming them 'One Mile North', 'One Mile West' and 'One Mile South'.
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"Thus, if I were to WALK my dogs, I could say that I walked 'One Mile North, One Mile West and One Mile South'.
"And yes, I would most definitely be back where I started: Forever Alone."
The answer
Talwalkar explained that there are in fact an 'infinite' number of correct answers to the riddle - but what is Musk looking for?
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The most common answer is the 'North Pole' because if you walk a mile north, then a mile west and a mile south you would end up walking in a triangle back to your starting position.
If you guessed it right, he'd then ask 'where else could it be?'.
Well, The Guardian reporter Alex Bellos provided a solution.
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He wrote: "There are an infinite number of places near the South Pole where walking a mile south, west and north returns you to exactly where you started. Consider the circle of latitude near the South Pole that has a circumference of one mile.
"From any point on this circle, walking one mile west along this circle will take you back to that same point. Thus any point a mile north of this circle of latitude is a solution to the problem.
"But there are more points too: Consider the circle of latitude that has a circumference of 0.5 miles. Any point a mile north of this circle is also a solution. Indeed, the solutions are any point one mile north of a circle whose circumference is (1/n) miles for all n."
Good luck job hunting!
Joe Yates