Jakow Trachtenberg believed that everyone is born with phenomenal abilities to calculate, he devised a set of rules that allows every child to make multiplication, division, addition, subtraction and square-root calculations with unerring accuracy and at remarkable speed.
Description:
Jakow Trachtenberg believed that everyone is born with phenomenal abilities to calculate, he devised a set of rules that allows every child to make multiplication, division, addition, subtraction and square-root calculations with unerring accuracy and at remarkable speed.