Short-cut MatheBook - 1984
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.
Publisher: New York : Dover Publications, 1984, c1969
Characteristics: 1 online resource (112 p.)