my new math trick ,Débuter Les Mathématiques, Compter, Apprendre À Additionner

This book is intended for any youngster (or maybe adult) who wants to overcome the challenge of the basic Times 9 Table or wants to be able to multiply two-digit numbers by 11 in their head. Yes, it takes a little practice but there are a couple of tricks to make it easier. Now, in 5 seconds, without the use of a calculator, or pencil and paper, what does 11 times 98 equal? The trick, using simple addition, is in this book.