Big Butts

Sir Mixalot likes big butts, and cannot lie. His identical, yet evil, twin, Sir Mixalittle hates big butts, and cannot tell the truth. One of them has arrived at your front door, bearing an important message for you. In order to profit from the information, you must know whether or not it is true. What single question can you ask, that will let you know with certainty to which twin you are speaking?

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