Trade Paperback. Condizione: VERY GOOD+. NY: Barnes & Noble Books, 1981. Trade Paperback. VERY GOOD+. Tight, faint age tanning of pages, clean and square. Owner's name inside front cover. "Easy to learn shortcuts: how to add long columns in your head, multiply, divide, and find square roots quicklyâ¦tricks, puzzlesâ¦" 157 pages.