This is a very difficult question to answer. However to better gauge your score, it would be good that if you can take up a mock test ( preferrably of gmat-prep, the free testing software provided by GMAC, which has two tests). Generally for students coming from the indian background have skewed scores with higher score in Quant than Verbal. If you can follow the Manhattan Prep guides & Official Guide by GMAC you can easily easily cross the 600 window. Find the below chart, this will help you gauge the score you should be targetting. The single most skill you should develop is time management for the exam.
Quant is generally covered is around class 10th mathematics with probabilty & permutation n combination.
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