Hey Anubhab,

Looking at the previous year's data and this year's statistics there's a possible chance of you getting into St. Xavier's Mumbai for B.Sc in Economics. You might not make it in the first merit but probably you'll make it in the second merit. 

You can go visit St. Xavier's Mumbai's official site to check last year's cut offs and merit list. You'll get an idea about it. I wish you all the best!