**About the Author**

*Jeff Sackmann has been helping students like you reach their GMAT score goals for nearly 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**and**Total GMAT Verbal**, as well as**1,800 practice GMAT math questions**and his**Guides to the Official Guide**.## Another 750+ Success Story

Stories like this one from Chad J. always make my day:

Thought I would drop you a line to let you know how much I appreciated both your website and Total GMAT Math. At the end of February I took the diagnostic test in the Official Guide and was shocked at how poorly I did on the Quant section (especially given my background in engineering). It was shortly thereafter that I stumbled onto your website as one of the folks searching for an answer to the question "am I allowed a calculator on the GMAT". As a part of what I call the 'calculator generation', my basic mental math skills were quite weak....and the answer I found was certainly not what I was hoping for! After reading a few of your articles I quickly realized that you knew exactly what the GMAT was all about and, more importantly, were able to relate this information to me in a way I could understand.On 28 February I ordered Total GMAT Math and went through it religiously (pun intended). I went to work first through Total GMAT Math, then took that information and worked through the questions that I did in the Official Guide. As I worked through the guide I also had a look at the vast majority of your articles on the website. These were the only three references I used in my five-week study period.

I wrote the GMAT exam yesterday, 9 April, and received a grade of 760 (Quant: 48, Verbal: 47). I certainly didn't think that was possible a little over a month ago, and I largely attribute my success to the clear and concise explanations you provide in both your book and online articles. If anyone asks me for advice in preparation for the GMAT I will let them know that your math bible is a must-buy, and your website a must-bookmark. I am convinced that anyone can be successful on the GMAT if armed with your math book, your online articles, and the official guide.