The Trachtenberg Speed System of Basic Mathematics by Jakow Trachtenberg
English | August 8, 2011 | ISBN: 4871877094 | 272 pages | EPUB, PDF | 7.83 MB
The Trachtenberg Speed System of Basic Mathematics is a revolutionary system for calculating and teaching basic math. Children, who had repeatedly failed in arithmetic until their parents sent them to learn this method, were able to perform amazing calculations within seconds. In one demonstration, a ten year old child, when asked to multiply 5132437201 times 452736502785, simply wrote on the blackboard the answer, 2323641669144374104785, in seventy seconds.