In the least surprising news we've heard all day, apparently being interviewed by billionaire Elon Musk is no walk in the park.
Apparently, one of his favorite riddles to ask engineers applying to work at SpaceX goes like this:
"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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That's what The Guardian reports Musk's biographer Ashlee Vance as revealing.
It's quite a well-known riddle in the tech world - prospective Microsoft employees have also been reportedly asked to solve it in interviews.
Take some time to think about the answer - what would you say?
Welll, there's one clear solution: the North Pole. Due to the curvature of the Earth, starting at the very top of the globe, going south for a mile, west and then north means you will travel in a triangular shape and end up at the same spot you started.
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Got it? Well, buckle up - because apparently Musk then likes to ask: "Where else could it be?"
Yikes. So it's not enough to have smashed one answer, because the Tesla billionaire then wants you to give more options - and it will seriously test your powers of reasoning.
Luckily, brainiacs are on hand to help - like Presh Talwalkar, who studied maths and economics at Stanford University and now posts math problems and brain teasers on YouTube with the account @MindYourDecisions.
Talwalkar has busted Musk's favorite brain teaser - take a look here:
According to Talwalkar, there are actually an 'infinite' number of answers to this particular puzzle.
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For example, if you drew a circle that was one mile in circumference around the Earth and started a mile north of any point on that line, you'd solve the riddle - and because you can pick any point above this line, there are countless answers.
If this makes your brain hurt, you're not alone. In fact, many of the comments under Talwalkar's YouTube video make it clear not everyone would pass this riddle - and some people are more concerned about trying to game the system.
"Your gym is exactly 1 mile south of your house. You walk 1 mile south to the gym. Hop on a treadmill and walk one mile to the west. Then walk home 1 mile north," is one tongue-in-cheek solution a commenter has suggested.
Another had a similar idea, and said: "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'."
Sure, they're not exactly mathematical solutions to this problem - but we bet Musk would actually have liked this kind of creative thinking.
We'll get our CV ready just in case...