Mistakes in mathematical reasoning can range from outlandish blunders to deep and subtle oversights that evade even the most watchful eye. This book represents the second collection of such errors to be compiled by Edward Barbeau. Like Barbeau's previous book, Mathematical Fallacies, Flaws and Flimflam, material is drawn from a variety of sources including the work of students, textbooks, the media, and even professional mathematicians. The errors presented here serve both to entertain, and to emphasize the need to subject even the most "obvious" assertions to rigorous scrutiny, as intuition and facile reasoning can often be misleading. Each item is carefully analysed and the source of the error is exposed. All students and teachers of mathematics, from school to university level, will find this book both enlightening and entertaining.

Table of Contents:
Preface; Part I. Geometry: 1. The asymmetric propeller Martin Gardner; 2. The asymmetric propeller revisited Gillian Saenz, Christopher Jackson, and Ryan Crumley; 3. Bracing regular polygons as we race into the future Greg W. Frederickson; 4. A Platonic Sextet for Strings Karl Schaffer; 5. Prince Rupert's rectangles Richard P. Jerrard and John E. Wetzel; Part II. Number Theory and Graph Theory: 6. Transcendentals and early birds Martin Gardner; 7. Squaring, cubing, and cube rooting Arthur T. Benjamin; 8. Carryless arithmetic mod 10 David Applegate, Marc LeBrun and N. J. A. Sloane; 9. Mad tea party cyclic partitions Robert Bekes, Jean Pedersen and Bin Sha; 10. The continuing saga of snarks Sarah-Marie Belcastro; 11. The map-coloring game Tomasz Bartnicki, Jaroslaw Grytczuk, H. A. Kierstead and Xuding Zhu; Part III. Flexagons and Catalan Numbers: 12. It's okay to be square If you're a flexagon Ethan J. Berkove and Jeffrey P. Dumont; 13. The V-flex, triangle orientation, and Catalan numbers in hexaflexagons Ionut E. Iacob, T. Bruce McLean and Hua Wang; 14. From hexaflexagons to edge flexagons to point flexagons Les Pook; 15. Flexagons lead to a Catalan number identity David Callan; 16. Convergence of a Catalan series Thomas Koshy and Z. Gao; Part IV. Making Things Fit: 17. L-tromino tiling of mutilated chessboards Martin Gardner; 18. Polyomino dissections Tiina Hohn and Andy Liu; 19. Squaring the plane Frederick V. Henle and James M. Henle; 20. Magic knight's tours John Beasley; 21. Some new results on magic hexagrams Martin Gardner; 22. Finding all solutions to the magic hexagram Alexander Karabegov and Jason Holland; 23. Triangular numbers, Gaussian integers, and KenKen John J. Watkins; Part V. Further Puzzles and Games; 24. Cups and downs Ian Stewart; 25. 30 years of Bulgarian solitaire Brian Hopkins; 26. Congo bongo Hsin-Po Wang; 27. Sam Loyd's courier problem with Diophantus, Pythagoras, and Martin Gardner Owen O'Shea; 28. Retrolife and the pawns neighbors Yossi Elran; 29. RATWYT Aviezri Fraenkel; Part VI. Cards and Probability; 30. Modeling mathematics with playing cards Martin Gardner; 31. The probability an amazing card trick is dull Christopher N. Swanson; 32. The Monty Hall problem, reconsidered Stephen Lucas, Jason Rosenhouse and Andrew Schepler; 33. The secretary problem from the applicant's point of view Darren Glass; 34. Lake Wobegon dice Jorge Moraleda and David G. Stork; 35. Martin Gardner's mistake Tanya Khovanova; Part VII. Other Aspects of Martin Gardner: 36. Against the odds Martin Gardner; 37. A modular miracle John Stillwell; 38. The golden ratio—a contrary viewpoint Clement Falbo; 39. Review of The Mysterious Mr. Ammann by Marjorie Senechal Philip Straffin; 40. Review of PopCo by Scarlett Thomas Martin Gardner; 41. Superstrings and Thelma Martin Gardner; Index; About the editors.