Trachtenberg Speed System of Basic Mathematics
Inbunden, Engelska, 1982
1 142 kr
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Beskrivning
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.
