Hello Aspirant

Your rank cannot be determined before the exam.

Because when rank are determined many factors play major role:

Like number of students who have appeared for the exam.No of students scoring same marks in paper or in a subject.

Still for your reference,I'm listing down previous year mark and the rank that they obtained,so that you have a rough idea of marks that you need.

1. 115-119:Rank 500-250
2. 90-114:2,500-2,501
3. 80-90: 5000-2501
4. 70-79: 5001-6500
5. 60-69:6501-8500
6. 42-59:8501-11000
7. Less than 30-20000

I hope this helps

Regards!