Hello dear

First of all it 75% aggregate criteria not 70% if you are talking about the NIT s, IIIT s and IIT s .

And this criteria is overall criteria not subject wise but you must have maths , physics and chemistry along with a language and one more subject. Even you have less than 75 marks in any subject but you have overall 75% above you are eligible.

Hope you get it.

Good luck

Hey there

The only academic criteria of jee mains is that the candidate should have passed or in class 12th that is appearing can take jee mains exam. As per the jee mains rank different colleges have different eligibility criteria such as For NITs , IIITs and CFTIs admissions, the candidates should have obtained a minimum of 75% aggregate marks or be in the top 20 percentile of their respective boards. For SC/ST category, a minimum of 65% marks required.

check the link

https://www.google.com/url?sa=t&source=web&rct=j&url=https://engineering.careers360.com/articles/jee-main-eligibility-criteria/amp&ved=2ahUKEwjToaOoqLjpAhUKfX0KHSsmCXsQFjAAegQIAhAB&usg=AOvVaw0Ddf__yVIUe0laa-JjEit-&ampcf=1

Good luck