This comic from XKCD is not only hilarious, but presents a remarkably GRE-like scenario:

So, here’s a question — what is the area of the “donut” shape in which the man in the comic is legally permitted to move?

Answer the question yourself before clicking “More.”

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The practical applications of math in the real world, from intrepid U.S. Post Office employee James Wu.

“This is a wall panel for an apartment building in Boston. It has five floors, and each floor has the same number of apartments. I have a package for #49–the buzzer doesn’t work very well, but they tell me to go up. What floor do I go to?”

Work out a solution before clicking “More”.

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Via Flowingdata via Raymond Johnson, credit to Ryan Grover.

If a multiple choice question has four answers, your chance of randomly guessing the right answer is 1 in 4, or 25% … right?

You’d think that — until you see that 25% is written twice.

So, since the correct answer appears twice, your chance of guessing correctly is 2 in 4, or 50% … right?

EXCEPT that if the correct answer is 50%, which only appears once, then the correct answer is actually 25% (since only one in four answers says “50%.”)

That’s sort of satisying — until you see that 25% is written twice.

So … (wait, this is hurting our heads!) since the correct answer appears twice, your chance of guessing correctly is 2 in 4, or 50% … right?

EXCEPT that if the correct answer is 50%, which only appears once, then the correct answer is actually 25% (since only one in four answers says “50%.”)

Whoa. (We’re nonplussed, flummoxed, addlepated, and just generally making a Keanu Reeves expression right now.)

Let’s stop here.