(related to Problem: The Sabbath Puzzle)

The way the author of the old poser proposed to solve the difficulty was as follows: From the Jew's abode let the Christian and the Turk set out on a tour round the globe, the Christian going due east and the Turk due west. Readers of Edgar Allan Poe's story, Three Sundays in a Week, or of Jules Verne's Round the World in Eighty Days, will know that such a proceeding will result in the Christian's gaining a day and in the Turk's losing a day, so that when they meet again at the house of the Jew their reckoning will agree with his, and all three may keep their Sabbath on the same day. The correctness of this answer, of course, depends on the popular notion as to the definition of a day — the average duration between successive sun-rises. It is an old quibble and quite sound enough for puzzle purposes. Strictly speaking, the two travelers ought to change their reckonings on passing the $180$th meridian; otherwise, we have to admit that at the North or South Pole there would only be one Sabbath in seven years.

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Project Gutenberg

  1. Dudeney, H. E.: "Amusements in Mathematics", The Authors' Club, 1917

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