Hello!

The selection process of an IIMs is extremely rigorous which requires lots of preparation specially in Ahmedabad Bengaluru n Calcutta.

As you have mentioned your 10th and 12th CGPA is fair enough. But for science stream student in graduation 70 percentile is required (For SC).

Go to the blw link

http://mbaden.com/iim-ahmedabad-selection-criteria/

Hope it helps !

Hey there

You have low academics score for IIMs and thus you need to have very good CAT score to get call form IIMs. Anything more than  97 percentile will be a safe for a good IIM.

check CAT cutoff

https://www.google.com/url?sa=t&source=web&rct=j&url=https://bschool.careers360.com/articles/cat-cutoff/amp&ved=2ahUKEwje2-rPx6XpAhVPzTgGHVMqBqUQFjAAegQIBRAB&usg=AOvVaw2IdCzY4rRdYaGrBXTO4MVx&ampcf=1

Good luck