hi,

see generally for bachelors degree level percentage calculation, internal exams and practical works marks is also considered to make  3 years course overall percentage calculation.  In official website of the tamil nadu dr ambedkar law university, there is no data available on marks calculation process. so I would suggest you to contact with exam center person of the respective college where you have completed your 3 years llb  courses about clarification of grade to percentage conversion rules.

hope you understand.