Contains over one hundred problems in which reasoning is required to reach the answer, ranging from easy to relatively difficult. Includes solutions.

The noted expert selects 70 of his favorite "short" puzzles, including such mind-bogglers as The Returning Explorer, The Mutilated Chessboard, Scrambled Box Tops, and dozens more involving logic and basic math. Solutions included.

Bizarre imagination, originality, trickiness, and whimsy characterize puzzles of Sam Loyd, America's greatest puzzler. Present selection from fabulously rare Cyclopedia includes the famous 14-15 puzzles, the Horse of a Different Color, and 115 others in various areas of elementary math. 150 period line drawings.

101 hand-crafted puzzles to teach the art of logic for Masyu, Slitherlink, Yajilin, Nurikabe, and Fillomino puzzles. The puzzles range from easy to medium in difficulty, and are perfect for beginners just getting started with logic puzzles. However, even seasoned pros may learn a thing or two from this clever collection of puzzles.

Karen is back with more lateral thinking puzzles and riddles! The difficulty level of these puzzles varies, but no matter how difficult you may find them to be, there is always an answer. Even if you answer the puzzle incorrectly, you may find it fun to explain why your answer could be correct as well. These are also great to use for a game night with friends and family. Quiz them to see how much they know. You never know what kind of answers you may get. All of these puzzles are lateral thinking puzzles-meaning you won't need a calculator nor pen and paper. All you need is your brain. The puzzles may be short or long, but they give you just enough information to figure out the answer. Make sure you don't over analyze them; otherwise, you may end up missing the answer all together.

This lucid introductory text offers both an analytic and an axiomatic approach to plane projective geometry. The analytic treatment builds and expands upon students' familiarity with elementary plane analytic geometry and provides a well-motivated approach to projective geometry. Subsequent chapters explore Euclidean and non-Euclidean geometry as specializations of the projective plane, revealing the existence of an infinite number of geometries, each Euclidean in nature but characterized by a different set of distance- and angle-measurement formulas. Outstanding pedagogical features include worked-through examples, introductions and summaries for each topic, and numerous theorems, proofs, and exercises that reinforce each chapter's precepts. Two helpful indexes conclude the text, along with answers to all odd-numbered exercises. In addition to its value to undergraduate students of mathematics, computer science, and secondary mathematics education, this volume provides an excellent reference for computer science professionals.