Many useful procedures explained and taught: 2-column addition, left-to-right subtraction, direct multiplication by numbers greater than 12, mental division of large numbers, more. Also numerous helpful short cuts. More than 8,000 problems, with solutions. 1945 edition.
Here's a sample of other books in this Dover category
Speed Mathematics Simplified by Edward Stoddard Entertaining, easy-to-follow suggestions for developing greater speed and accuracy in doing mathematical calculations. Surefire methods for multiplying without carrying, mastering fractions, working quickly with decimals, handling percentages, and much more.
A Refresher Course in Mathematics by F. J. Camm Readers wishing to extend their mathematical skills will find this volume a practical companion. Easy-to-follow explanations cover fractions, decimals, square roots, metric system, algebra, more. 195 figures. 1943 edition.
