Please recommends books I can get, from amazon? I need to get really good at mental math and math by hand, because I'm taking an exam soon without a calculator.
5 Answers
One classic text is The Trachtenberg Speed System, which actually has an amazing history: Trachtenberg created the tools for the book (speed mathematics, including multiplication) while in a Nazi concentration camp, without the use of paper or a writing utensil.
The Wikipedia page gives a pretty good overview of the book, and there is a bit about Jakow Trachtenberg on Wikipedia as well.
p.s. Don't let the \$91 price on Amazon.com worry you; you can find many used copies for less than \$10.
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I got the kindle edition. – Algific Jul 31 '11 at 20:43

This was magic, can't believe I didn't learn this in school. Thanks. – Algific Aug 01 '11 at 04:35

@Algific  glad you liked it. I didn't know there was a Kindle edition. – Chris Gregg Aug 01 '11 at 13:54

Glad to hear that it's still available. I have a very old copy. – DanielWainfleet Sep 16 '15 at 22:32
If you're looking for books about rapid arithmetic calculations, then these two books might be what you're looking for. They are Speed Mathematics and ShortCut Math, which will cost you less than $15 for the both of them from Amazon. I bought them for my little sister a few years ago, since she wanted to learn some mental math tricks, and she said that they were both pretty good.
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I also need to do multiplication and division with decimal numbers by hand, is that also in those books? – Algific Jul 31 '11 at 19:28

I believe they did. They had everything that she had been interested in learning and I'm sure that included decimal multiplication/division. – Michael Banaszek Jul 31 '11 at 19:35
The best book for mental math and math by hand is Vedic Mathematics by Bharati Krsna Tirthaji. Just search in Google and Amazon.
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On the website http://www.mathmagic.com/ you can find some tricks for mental arithmetic.
They are divided into various categories, like Multiplying numbers, Multiplying strategies, Basic memorization, etc.
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