Hi,

JEE Advanced rank is based on Marks not on percentile because it's paper happens in same day for everyone. Every year, the Patten of JEE Advanced changes due to which is difficult to predict what specific marks should be enough to secure seat in IITs. However if we go by general trend from past years, If a SC Category student scores 10-20 marks above General category cutoff, then the student would secure a seat in IITs.

I hope this will solve your query.

Thanks!!!!