Mental Calculation Wizard: Amazing High-Speed Mental Calculation Techniques. Arthur Benjamin (Author), Michael Shermer (Author), Hiroshi Iwatani (Translator) "So that's how it's done?" What are the high-speed mental calculation techniques that make complex calculations easy at amazing speeds? From those who are not good at calculations, to those interested in mental calculation, to readers aiming to become "mental calculation wizards." Everyone will love mental calculation!! This book is by Dr. Benjamin, a university math professor and professional magician, who clearly teaches groundbreaking mental calculation techniques -- how to perform complex calculations incredibly quickly and easily -- from the very beginning. These techniques can be easily mastered by children, the elderly, and even those who are not good at math. It's also perfect for brain training. Let's get started now.