How to Calculate Quickly: Full Course in Speed Arithmetic

Do you want to double or triple the speed with which you
calculate? How to Calculate Quickly is a tried and
true method for helping you in the mathematics of daily
life—addition, subtraction, multiplication, division, and
fractions.
The author can awaken for you a faculty which is surprisingly
dormant in accountants, engineers, scientists,
businesspeople, and others who work with figures. This is
“number sense”—or the ability to recognize relations between
numbers considered as whole quantities. Lack of this number
sense makes it entirely possible for a scientist to be
proficient in higher mathematics, but to bog down in the
arithmetic of everyday life.
This book teaches the necessary mathematical techniques that
schools neglect to teach: Horizontal addition, left to right
multiplication and division, etc. You will learn a method of
multiplication so rapid that you’ll be able to do products in
not much more time than it would take to write the problem
down on paper.
This is not a collection of tricks that work in only a very
few special cases, but a serious, capably planned course of
basic mathematics for self-instruction. It contains over
9,000 short problems and their solutions for you to work
during spare moments. Five or ten minutes spent daily on this
book will, within ten weeks, give you a number sense that
will double or triple your calculation speed.