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## Video: OG Diag Explanation: PS #13

###### July 21, 2010

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Here's another video question explanation. This one deals with question #13 from the Official Guide math diagnostic. It's a problem that gives lots of people fits, but doesn't have to be that hard.

Watch and learn!

Remember, I've created (print) explanations to every Quant problem in The Official Guide for GMAT Review and The Official Guide for Quantitative Review. Find out more about those resources here.

**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! |