I love this little book because it is convenient and well built: the point to understand the application and corrected exercises. Me refractory following calculation since elementary school, I enjoyed the simplicity and clarity of explanation and I started to use it in my life everyday. I wish that in my time, we explain the calculation in this way. Thank you to the author for writing this book for people like me. I hope others will soon follow such tomes on percentages, fractions, positive and negative powers, negative numbers etc. In short, everything I did not understand the last 40 years ... and who m 'handicaps when I read the papers or watch TV ... In any case, do not hesitate to buy this mental math book it is convenient for all ages!
