Question This two-player game begins with 10 stones laid out in a row.   The players take turns removing stones from the row.

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Question One, two, three, four… A waterdrop falls from a skyscraper’s balcony every 0.5 s. The first drop hasn’t

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Question In this game of Nim, Abdi and Suri are playing with one heap of 11 stones and another heap of 9 stones. The game is playe

Question To celebrate the end of exams, three couples met for a dinner. They’re about to take seats at a round table for six

Question This figure includes 20 line segments. Using these rules:   you can start at any intersection on the figure, you can