Ann Cutler (Reihenfolge der Bücher (Chronologisch))

The Trachtenberg speed system of basic mathematics translated and adapted by Ann Cutler and Rudolph McShane

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 '

1962