My challenge to improve Maths

Hi everybody,

I took GMAT last Friday and I got a nice 660 (Q43 and V39). I'm quite satisfied with it, especially considering that I'm Spanish and I was afraid I couldn't manage with verbal. Anyway, I want to give another try in one month so I have a chance to get into MIT/Berkeley, which are my top universities.

My target is at improving my Maths. I know I can do it. Actually, I panicked in the test and I spent about six minutes trying to solve a 3 variable equation!!! So I guess in the end it's about strenghtening my base of maths, especially in Prob, Permut, Comb and inequalities (for DS). I know that if I feel confident with them I'll improve a few points and that will get me at least a 680-700 (which is my target). So here is my question, does anyone know a good book and/or web with those neeeded basics? I found some webs, but I guees I'm old school and I'd feel like studying with a book.

My prep material has been MGMAT (they have an excellent course if you want a 650, but if you want to score higher than that you need to take its "advanced" courses), KAPLAN800 (Maths too easy), OG, some tests a Taiwanese friends gave to me and, of course, this forum, which is GREAT.

You know, after one month and half studying full time (I came to the US only to prepare for GMAT and TOEFL) I'm really satisfied with my improvement. I studied undergraduate business and I felt that my studies didn't help me at all with GMAt. You know, some people have an engineering background, so they do great in maths and seem to face more difficulties with verbal. On the other hand, some other people have social background, so they can do better at verbal. And me...well... I did some maths at the university, but not too much. And I'm a foreigner! 6 weeks ago I even didn't remember how to substract and completely ignored most of English idioms.

So next month (after finally a deserverd weekend off) it's going to be tough: applications, TOEFL (I take it in two weeks, but I'M NOT WORRIED AT ALL: it's a joke compared to GMAT) and improving GMAT.

Thanks!!! It's great to know that there are some people who have been through the same situation. And right now I'm going to enjoy the few free hours left before tomorrow I begin again with GMAT!!!