Your score seems normal Jenil.If your CAT percentile is as per cutoffs than IIM-Calcutta will call you.There is no worries about the low marks in 10th ,12th marks to know follow this link:https://youtu.be/riHLPlUl87s
To know cutoffs of IIMs folllow this link:https://bschool.careers360.com/articles/iim-cutoff
Hope this helps you.
Good luck..
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