Dear Deepak,

80.6% is considered a good marks if you want to get admission for B.SC Math in Calcutta university. Marks of Math in your board would not really matter and having an average marks of 50% in math is more than enough. Your selection will completely be based on your merit of the qualifying examination from a recognized board and more on the merit of the entrance examination organized by the university itself. You have to clear the entrance exam with a good score to fix your spot and the 80.6% in your boards will act as an add-on advantage.

All the best for your future