Whoa. From Math Whiz Breaks Calculation Record:
A 38-year-old with degrees in psychology, education and computer science needed only 11.8 seconds to calculate the 13th root of a 100-digit number in his head, setting a new record, organizers said.
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“I first think of an elegant problem-solving algorithm and the result comes immediately,” said Mittring, who beat the previous record of 13.55 seconds, set by the Frenchman Alexis Lemaire in 2002, according to organizers of the Tuesday night event.