Subjects like Maths, Science, Economics and History may be related to some extent, however, their application varies. Economics makes use of a lot of mathematical concepts but the very use of economics goes far beyond simple calculations. Economics is a science in itself and therefore requires practical and analytical skills. History, on the other hand, is a descriptive subject which delves into the past events. These past events could be political events, economic events and so on.

So, it would be completely unfair to have all these related but different subjects having the same syllabus across India for entrance examinations. To pursue further studies in any of the above disciplines, a student must require a basic/undergrad level of minimum education on these subjects. Students must be tested on the basis of their own domains and not on the basis of a common syllabi.

To provide a level playing field, a section on aptitude and language skills may be added. However, for higher studies, it is essential that the individual clears the minimum eligibility criteria. Thus, entrances for higher studies must have a syllabi which accurately deals with the disciple it is designed for, and not a common syllabi as you’ve mentioned in your question.