Madras Institute of Technology, Anna University

The rules for 2019 JEE will be published by the CBSE by the end of 2018. But, according to the rules by the CBSE for JEE 2018, a student wishing to appear for JEE needs to satisfy a criterion of 75% in his or her class 12 boards or in an exam equivalent to the same. This is one of the efforts to reduce the number of applicants for JEE, thus, in turn, reducing the competition. So yes, if a candidate has an aggregate score less than 75% in his or her class 12 board exams of any class 12 equivalent examination, he or she is not eligible for giving the JEE and this, in turn, is not eligible for a seat in an IIT or an NIT. According to your query, the student must score an aggregate of 75% and not 75% score in each subject. If you somehow could not manage to score 75% or above, you can take a drop, and study for an entire year, and then give the exams again. According to me, this is a tedious process as it would require that you enroll in some college, complete all the board prescribed practicals all over again, write all the assignments again and complete all the submissions. The other alternative to this is that you appear for the correctional examination which is normally for the students who have failed in a subject or two. You will only need to submit all the journals that you have already written, and appear for the practical exams.