My first and most important suggestion would be to not take the GMAT in two months. Three hours a day for two months is not enough for a 100-point improvement, especially since you are starting at a 550. According to MBA.com, the average study time for someone scoring a 600-690 is 106 hours.
I would strongly suggest taking more time each day or studying over another one to two months.
For quantitative, the MGMAT books
are excellent. Have a look at those. Another book that gets great reviews is Total GMAT Math
. Where on the quantitative section are you struggling?
The MGMAT SC
is definitely the best SC book, so you are off to a good start there. I would also suggest PowerScore CR
Other than studying those books, get all of the official guides and stay active on the GMAT Club forums. I would suggest working through all of the MGMAT books
and try answering three questions a day on GMAT Club.
I hope that helps
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