Hi Krishna,
St. Xavier's issued different cut off list for different courses. Admission in courses like b.com is done on merit base i.e marks obtained in 12th board. And admission in courses like bba and other are based on entrance base. You have scored good marks in 12th so you will get admission in this if you want to pursue b.com and for any other course you will have to give entrance exam.
Hope this will help you.
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