"A man writes the same number, and nothing else, on 20 sheets of paper. Why?" "A man went around the world in a ship. Yet he was always in sight of land. How co

Presents a collection of puzzles designed to challenge the way people think and see, and includes an answer key.

It's only logical--boost your brainpower with 150 logic puzzles for adults. It's time to give your mental muscles a real workout! Stuffed full of clever and cun

Lateral thinking is the key to solving these tantalizing puzzles. Packed with hundreds of brain teasers and mathematical problems, the book will test kids' powe

Problems block and slow down your progress; here’s how to overcome them–simply, efficiently and effectively. This book offers straightforward, empowering sc