The Trachtenberg Speed System of Basic Mathematics
First developed during WW2, the Trachtenberg speed system makes possible high-speed arithmetical calcula tions with a remarkable degree of accuracy. The system has e ven been known to beat computer calculations - in some insta nces - in terms of speed '
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LibraryThing ReviewUser Review - GrdnDelite - LibraryThing
System designed to allow very fast multiplication of numbers by adding them in various combinations. Also addresses other operations. It's all real and I'm forever in debt to the teacher who had us ... Read full review