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.

The Trachtenberg Speed System of Basic Mathematics 1982, Praeger, Westport, CT

ISBN-13: 9780313232008