The Trachtenberg Speed System of Basic Mathematics

ISBN-13: 9780313232008 / Angielski / Twarda / 1982 / 272 str.

Ann Cutler; Rudolph McShane; Rudolph Matas McShane

Opis

The complete system of the Trachtenberg method of mathematics which makes possible high-speed arithmetical calculations with a remarkable degree of accuracy.This method is not only speedy but simple. Once one has mastered the rules, lightning calculation is as easy as reading a story. It looks like magic, but the rules are based on sound logic.