About the Author

Jeff Sackmann has been helping students like you reach their GMAT score goals for a decade. Jeff began as a star tutor and classroom teacher for a big test-prep company. Since 2006, he has focused on developing the best materials in the industry, saving you time, money, and stress.

Based in New York City, Jeff has created many resources for GMAT preparation, including the popular Total GMAT Math, Total GMAT Verbal, and GMAT 111, as well as 1,800 practice GMAT math questions and his Guides to the Official Guide.