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nydus/The Canterbury Puzzles, and Other Curious ProblemsPublic

Henry Ernest Dudeney collects a wide variety of original mathematical and mental puzzles into this volume. The book features an introductory essay on the nature of puzzles and provides solutions for all problems at the end.

Page 219 of 307
Table of Contents

46 .— The Riddle of the Crusaders.

The correct answer is that there would have been 602,176 Crusaders, who could form themselves into a square 776 by 776; and after the stranger joined their ranks, they could form 113 squares of 5,329 men—that is, 73 by 73. Or 113 × 732 - 1 = 7762. This is a particular case of the so-called "Pellian Equation," respecting which see A. in M., p. 164.

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