Clear, concise compendium of about 150 timesaving math short-cuts—faster, easier ways to add, subtract, multiply and divide. Each problem includes an explanation of the method, a step-by-step solution, the short-cut solution, and proof and an explanation of why it works. No special math ability needed.
By using the simple foolproof methods in this volume, you can double or triple your calculation speed--even if you always hated math in school.
The short cuts in this book require no special math ability. If you can do ordinary arithmetic, you will have no trouble with these methods.