I am assuming you are from general category. Based on your overall academic profile, you will need to score atleast 99.9 percentile to get a call for the next round.

All the best!

It depends for which course you want to take admission in IIM C.

Assuming that you are asking for PGDM course then
Candidates will be short listed based on CAT score, past academic performance, personal interview and WAT rounds.

You can check the complete details of requirement and selection process in the link below:

IIM C Admission Process

Aim scoring above 99 percentile to get admission in this college.

You can even check the complete weightage of class 10th, class 12th and graduation academic performance evaluation.

CAT entrance is the must condition so make sure you do not forget to fill the form. The last date has been extended to 25th September.

You can apply from here
CAT Form

Good Luck.