BBA Maths

Yes, you can study MSc maths after BBA.
However, I won't recommend going for it, as if you really have a passion for maths, doing other courses in maths specialization would be better for your career.
All the best.

Maths is not important for BMS in Jai Hind.

There are 87 BBA College in Kolkata, Have a look at the Shiksha link and check their eligibility criteria:
https://www.shiksha.com/bba/colleges/bba-colleges-Kolkata
Good Luck.

No, Maths in BBA isn't that much difficulty. A basic concept were teacher. Don't worry. It's not so difficult. The students who haven't maths in +2 can manage easily.

Check out the colleges in the UK that accepts students to do BBA course without Maths. There would be some colleges that would take your admission only if you meet their eligibility criteria.

ELIGIBILITY CRITERIA:
*Candidates should pass +2 (Karnataka PUC/ISC/CBSE/NIOS/State board) in any stream (Humanities, Social Sciences, Commerce & Management, Sciences) from any recognised Board in India.
*Candidates pursuing international curriculum must have AIU approval and must obtain a grade of not less than 'C' or its equivalent. *Candidates appearing for the +2 examinations in March-May 2018 may apply with their class X and XI marks.

Dear,
A student, who has completed +2 with Science having Mathematics as a compulsory subject and has covered it sincerely, can smoothly handle BBA in Maths & Accounts.
Best wishes.

Check the below link for B.Sc Maths:
https://www.shiksha.com/science/colleges/b-sc-mathematics-colleges-Pune
You can request for the brochure of various colleges.