Hey,

According to IIT-JAM eligibility criteria, General/OBC students are required to score at least 5.5/10 or 55% aggregate in their graduation.

If your marks are less than 60% but more than 55% you can definitely fill in for the IIT JAM, but some colleges have a criteria of minimum 60% in their graduation for admissions into the offered courses(For General candidate), for that you need to check the college's website. For more information regarding IIT JAM, follow the link; IIT JAM