In a lively show, mathematician and magician Arthur Benjamin races a team of calculators to figure out 3-digit squares, solves another massive mental equation and guesses a few birthdays. How does he do it? He’ll tell you. (15:18)

Learn mental math multiplication tricks Learn to multiply large numbers in your head. Uses benchmark numbers. Suggests practicing mental math to get better at it. Captions appear on the screen. (2:46)

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