Customer Rating: 
Summary: It does what it says...
Comment: Long collection of exercises to improve your mental calculating ability. This book will keep you busy for quite a while. It's slim but there's a lot of exercises in it. It will give you eough familiarity with numbers to do fairly large multiplication and division (let alone addition and subtraction) in your head. Fractions included. Requires no advanced math skills of any sort. Presupposes a knowledge of basic caluculation, that's it. No algebra, geometry etc.
Summary: It does what it says...
Comment: Long collection of exercises to improve your mental calculating ability. This book will keep you busy for quite a while. It's slim but there's a lot of exercises in it. It will give you eough familiarity with numbers to do fairly large multiplication and division (let alone addition and subtraction) in your head. Fractions included. Requires no advanced math skills of any sort. Presupposes a knowledge of basic caluculation, that's it. No algebra, geometry etc.