To be honest, your class 12th marks doesn't matter that
much as they only need to make you eligible for a particular
exam.
But, you'll have to work pretty hard to offset that 12th score.
To be good enough for you will most importantly need 99.5+
percentile in CAT and good enough marks in your graduation
too.
Though you have to keep in mind that there are some top
IIMs which are strict for their 10th, 12th criteria, do not
keep many hopes from them.
Good luck!
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