Based on your 987 marks in intermediate and 84.6 percentile in JEE, you may have a chance to secure a seat in the Computer Science and Engineering (CSE) branch at SASTRA University. The university considers both your 12th marks and JEE scores for admission. In previous years, the cutoff for CSE was around 987 marks in intermediate, and your score is close but slightly below this threshold. While admission is not guaranteed, there may still be opportunities, especially if you belong to a reserved category. It's best to check the official SASTRA University website for updates on the admission process and cutoffs.