Poor Benedict Cumberbatch. Just because he plays brilliant detective Sherlock Holmes on TV, everyone expects him to be some kind of genius, when the truth is he struggles to comprehend basic arithmetic. 

OK, not really, but that's the joke that the "Sherlock" star and unlikely sex symbol gamely played along with during a visit to "Sesame Street." There, he came face to face with the dastardly "Murray-arty," who presented the actor with the "mind-bending challenge" of determining whether there were more apples or oranges on the table in front of him. (Seriously, that whole mystery with the soldier in "The Sign of Three" was a cakewalk compared with this.)

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"You're the super sleuth," said Murray-arty. "Figure it out."

Cumberbatch resisted at first, insisting, "I'm really just an actor." Eventually, though, with some help from the Count (not Watson), he was able to enter his own mind palace and get to the bottom of the mystery. 

We won't spoil the fun by revealing the answer. 

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