ISBN10: 0486246116 ISBN13: 9780486246116 Publisher: Dover Pubns Published: Apr 1 1984 Weight: 0.30lbs. Height: 8.25" Width: 6.00" Depth: 0.25" Language: English
Clear, concise compendium of about 150 time-saving math short-cuts features faster, easier ways to add, subtract, multiply, and divide. Each problem includes an explanation of the method, a step-by-step solution, the short-cut solution, and proof, as well as an explanation of why it works. No special math ability needed.