Maths or science or arts doesn't matter, you need interest, dedication, focus, perseverance. As you want to become an IAS officer you will be needed to give an UPSC exam conducted by the Union Public Service Commission.  The UPSC exam is conducted every year in India for the various posts like:

1. Indian administrative service
2. Indian Police Service
3. Indian Revenue Service
4. Indian foreign Service etc.

An IAS post is the first class officer’s post offered by the Central Government of India.  They eligibility criteria is that a student should have completed there graduation degree completed from any stream or student who is in the last year of their graduation degree can also apply for the exam.  The UPSC exam is conducted in 3 stages Prelims, mains and Interview.  The prelim exam is objective based and this conducted in June, mains exam is written exam and this conducted in October.  Students qualifying the mains exams are called for the interview in the month of March-May.

The minimum age to apply is 21 years & the Upper age limit as a general category is 32 years , for OBC it is 35 years and for SC-ST it is 37 years .

Good Luck!