100 tough story teasers for the jaded. More difficult algebraically than typical puzzles, and ideal for confirmed puzzle fanatic, but appendices help less experienced. Step-by-step solutions to all 100 puzzles. Also 40 new alphametics — solvable by simple arithmetic and logical reasoning — with answers, and two sample solutions.
The Stanford Mathematics Problem Book: With Hints and Solutions by G. Polya, J. Kilpatrick Based on Stanford University's well-known competitive exam, this excellent mathematics workbook offers students at both high school and college levels a complete set of problems, hints, and solutions. 1974 edition.