I find this book “25 Math Short Cuts” very entertaining. I have been teaching Mechanical Engineering here in Cebu Institute of Technology-University (CIT-U) for 15 years. In an engineering school like ours, students are highly dependent on their calculators to compute even basic arithmetic operations. I always get the kick out of their amazement when I calculate mentally engineering formulas faster than they can get the answers in their calculators. Little do they know that the assumed values used in the formulas are special patterns (like complementary numbers and squaring numbers ending in 5). I never failed to impress them when I teach them some of the shortcuts I got from this book.
In my public seminars I always inject some of these shortcuts when we resume discussions after lunch break. They always jump back to life when I teach them multiplication near a base, division by 9 and multiplication of complementary numbers, among others.
Like me, I’m sure many students or seminar participants would find this book both interesting and entertaining. Congratulations to the author for this timely and useful book.