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**1,800 Practice Math Questions**

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## Video: Multiply by Nine (Faster)

###### March 13, 2012

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I love mental math tricks. On the GMAT, you need to compute quickly. Here's a technique you can use to quickly multiply any number by 9. Enjoy!

**About the author:** *Jeff Sackmann has written many
GMAT preparation books, including the popular Total GMAT Math,
Total GMAT Verbal, and GMAT 111. He has also created
explanations for problems in The Official Guide, as well as
1,800 practice GMAT math questions.*

Total GMAT Math
The comprehensive guide to the GMAT Quant section. It's "far and away the best study material
available," including over 300 realistic practice questions and more than 500 exercises! |