The Best Statistics Question EVER

by Jen Dziura Nov 7, 2011

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.