This is a so wonderful place! please give me some advice.

This is a place moving me and inspiring me! I wish I had found this place earlier!

Oppressed by livelihood, I yesterday decided to overcome GMAT. Actually, that moment all I knew about GMAT was the four letters: G, M, A, and T. Today, seeing some posts here, I got a little impression about what it is. Thank you guys very much!  Anyway, I got a problem and hope you guys could help me out.

My problem is about Math. I totally forget them all, for I have graduated from my university many years. Last month, I reviewed half of a calculus book (English version, North America university level) on other purposes, feeling very well and picking up some memories on High school math; Anyway, My math level is a far cry from that of GMAT requests, and I am, so far, in deep blank in statistics.

According to my math situation, which math books should I set about using? Any tips would be much appreciated!