国外很经典的一部算数速算技巧指导宝典！（一共涉及150种速算技巧，加减乘除都有哦！）
Can you multiply 362 x .5 quickly in your head? Could you readily calculate the square of 41? How much is 635 divided by 2½? Can 727,648 be evenly divided by 8?
你能在脑子里快速地乘以362x.5吗？ 你能很容易地算出41的平方吗？ 635除以2.5等于多少？ 727,648能除以8吗？
If any of these questions took you more than a few seconds to solve, you need this book. Short-Cut Math is a concise, remarkably clear compendium of about 150 math short-cuts — timesaving tricks that provide faster, easier ways to add, subtract, multiply, and divide.
如果这些问题中的任何一个花了你几秒钟以上的时间去解决，你需要这本书。 简明数学是一个简洁的，非常清晰的约150个数学简明-节省时间的技巧，提供了更快，更容易的方法，加法，减法，乘法和除法。
By using the simple foolproof methods in this volume, you can double or triple your calculation speed — even if you always hated math in school. Here's a sampling of the amazingly effective techniques you will learn in minutes: Adding by 10 Groups; No-Carry Addition; Subtraction Without Borrowing; Multiplying by Aliquot Parts; Test for Divisibility by Odd and Even Numbers; Simplifying Dividends and Divisors; Fastest Way to Add or Subtract Any Pair of Fractions; Multiplying and Dividing with Mixed Numbers, and more.
通过使用这卷书中简单的万无一失的方法，你可以将你的计算速度提高一倍或三倍——即使你在学校里一直讨厌数学。 以下是几分钟内你将学到的非常有效的技巧:增加10组； 无进位加法； 不借用的减法； 乘以等分部分； 奇数和偶数可除性检验； 简化被除数和除数； 加法或减法任何一对分数的最快方法； 用混合数相乘和相除，等等。
The short-cuts in this book require no special math ability. If you can do ordinary arithmetic, you will have no trouble with these methods. There are no complicated formulas or unfamiliar jargon — no long drills or exercises. For each problem, the author provides an explanation of the method and a step-by-step solution. Then the short-cut is applied, with a proof and an explanation of why it works.
这本书的捷径不需要特殊的数学能力。 如果你能做普通的算术，你就不会有这些方法的麻烦。 没有复杂的公式或不熟悉的行话-不再操练或练习。 对于每一个问题，作者都给出了一个方法的说明和一个逐步的解决方案。 然后应用该捷径，并对其工作原理进行了证明和解释。
Students, teachers, businesspeople, accountants, bank tellers, check-out clerks — anyone who uses numbers and wishes to increase his or her speed and arithmetical agility, can benefit from the clear, easy-to-follow techniques given here.
学生、教师、商人、会计师、银行出纳员、结帐员——任何使用数字并希望提高速度和算术敏捷性的人，都可以从这里给出的清晰、易于理解的技巧中受益。
