Hi Dear,

IIM Calcutta final admission depends on composite score based on following points:

CAT Score: 30 points

Written Ability Test: 10 points

Personal Interview: 48 points

Academic Diversity (non-Engg): 4 points

Work Experience: 8 points

If you are getting a composite score of 78, then you might find some difficulty for final selection.

You can check the link below for more details:

https://bschool.careers360.com/articles/iim-calcutta-admission-criteria

good luck