I m B.Sc graduate.I m very good in Maths and i want to became a Gazetted officer.which Exam i have to pass to became a gazzetted officer

there are public service commission exams conducted by States,followed by interview and with the usual reservations.you have to appear for them.

TO Become the Gazetted Officer you have to Clear the UPSC Civil Service Examination. After Clearing Civil Service Examination person become the class - 1 officer in Indian Government else you can try for SSC Combined graduate level Examination in which you get the post of class-2 officers in Indian