how much mark needed in 12th class

Suriya, the eligibility criteria for different institutes and colleges are different from each other. Some have a particular percentage criterion which needs to be satisfied in order for a candidate to be eligible to apply to any course in that college whereas others may only need a candidate to be passing in Class 12 or any equivalent examination. As you have not specified the name of the institution or the entrance exam you are interested in, it is very difficult to answer your query. Kindly rewrite your question mentioning the details of the exam or college or you can write a comment and I would surely try to find you a solution to your problem.