Science

MS is an abbreviation used for Master of Management Studies and is a two-year professional course in management. The course is offered in 4 successive semesters. The course provides an insight into the core as well as specialised subjects in management. Specializations are usually offered in areas of finance, marketing, operations, human resources and systems. The course is much similar to other professional management courses like MBA or PGDM. The course study offers adequate knowledge and practical skills in a candidate to plan and optimize resources for maximum productivity.
Advantages or Benefits of Master of Management Studies Course
The professional course study helps candidate to gain adequate skills in supervision and control of business activities and to plan and handle employees at the same time. The same acts as a platform to increase the knowledge base of the candidate and to acquire entrepreneurial skills. The course study acts as base work for one to have doctoral level courses in Management. Further the candidate can obtain a lucrative career in their interested domain of specialisation.
Eligibility required for Master of Management Studies Course
Those who have completed their graduation from any of the recognised institution are eligible to undergo the course. The graduation must be obtained in any discipline with at least 50% marks. The candidates who pursue their final year graduation are also eligible. The candidate has to pass through certain common entrance exams to get eligible for the course. MHCET is the most common entrance exam for MS course, since most of the institutions are located in Maharashtra. There is no entrance test in institutions like BITS-Pilani where the course is offered as an integrated one immediately after 12th class studies. Those who pass the entrance exam have to attend group discussions or interview as part of the selection process.

No, if you are not good at maths, economics is not for you either. However, if you like economics so much, that should motivate more interest in maths. From what you describe, I do not think you are poor in maths. Your learning experience in high school was not pleasant, but that should not be a reason for you not to try again. Try approaching again with a fresh mindset and you may find yourself turn over a new leaf with maths.
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No, without mathematics as main paper, you are not eligible to get admission in Economics (Hons) course in best colleges.
As in Delhi University and other best universities, it is necessary to have mathematics as the main paper to get admission in Economics (Hons) course.