Dear Rahul 

If you want to get admission in DTU or IIIT Delhi , the eligibility criteria set by JEE is that a candidate must score 80% or above aggregate in his best 5 and 80% or above in Mathematics in his class 12th board where Chemistry, physics, mathematics and English are the core subject.  But as you have stated that you have OBC reservation,  there is a 5% relaxation for you in the Marks. So you are eligible . Good luck