Mattetriks på null komma niks

Forget about the calculator, this book will teach you how to do quick calculations in your head or with a pencil. To count faster, it is enough to think a little differently, its author Yngve Vogt, a Norwegian journalist for the scientific journal Apollon and a fan of mathematics, is sure. You will learn about simple and fun methods of quick counting, for which you only need to know basic arithmet...