Hi,

In accordance to the previous year reports,the cutoff of OBC NCL was around 80–85 ,so this time considering the increase in seats and less number of applicants going for IAT,a score of 75 would be able to secure a seat in IISER. However the cutoff varies every year and also statewise. So you may definitely try for respective college. Hope it helps. For more information refer to

https://engineering.careers360.com/exams/iiser-aptitude-test