This review is not intended to tell you lots about the book, only about who the book is aimed for. I bought this book with the expectation that it would have lots of puzzles suitable for the "average Joe", or there abouts and would require some level of Mathematical thinking so would be nice, light hearted practice for my students ( I am a secondary school maths teacher). The level and style of the puzzles varies, but the majority of problems are aimed at those who are capable of attaining grade A at GCSE Mathematics and it does have some fairly complex solutions. The layout of the book is also fairly old fashioned. It was first published in 1971 and the font and presentation is in line with what you would expect of a book published at that time. If you are looking for puzzles involving a higher level of mathematical thinking and a variety of styles of problems however then this book does suit this purpose.
In summary, this book may be great or fairly useless, depending on for what purpose it is wanted.