The Trachtenberg Speed System of Basic Mathematics - Jakow Trachtenberg

Do high-speed, complicated arithmetic in your head using the Trachtenberg Speed System.Ever find yourself struggling to check a bill or a payslip? With The Trachtenberg Speed System you can. Described as the 'shorthand of mathematics', the Trachtenberg system only requires the ability to count from one to eleven. Using a series of simplified keys it allows anyone to master calculations, giving greater speed, ease in handling numbers and increased accuracy.Jakow Trachtenberg believed that everyone... Zobrazit více