hi,

see the eligibility criteria for admission to jamia milia islamia b.tech course is candidates must secured at least of 55% marks in pcm and must have studied physics , chemistry and mathematics as a compulsory subject in 12th course.

now see the eligibility criteria differs as per college or university wise, but it would be tough for admission with 45% score if you are from general category. generally the sc/st/ obc like reserve category candidates has some marks relaxation.

so my suggestion is check the official brochure before applying to any college.