CAT

It totally depends on your choice of institution you want to go in. In some colleges, they take you on the basis of your National Level Examination ( CAT/MAT ) score while on the other hand some institutes conduct their own entrance exam. However, General Eligibility for MBA includes :
1. Minimum aggregate score of 50% (45% in the case of the candidate belonging to reserved categories) in his/her graduation or degree exam from a recognised university.
2. Qualify an Entrance Examination like CAT/MAT/ XAT/CMAT etc. - Some of the universities conducts their own entrance exam too.
3. Qualify Personal Interview as conducted by different institutes. Top Institutes from where you can pursue MBA :
1. IIT Madras, Chennai
2. Lovely Professional University, Punjab
3. Xavier Labour Relations Institute, Jamshedpur
4 Nirma University, Ahmedabad
5. Kristu Jayanti College, Bangalore
6. NMIMS, Mumbai
7. ICFAI Business School, Hyderabad.

Hi,
I would suggest you not to practice a topic for more times if your concept in that particular topic is clear, you should practice more questions on the topics were you are weak or you take more time than the required time, I will also suggest you to keep track of your problem solving time to check that you do not consume more time. Start taking a mock a week and analyze it. You would have covered most of the basics through it. Therefore, from you should, take 2 mocks a week and analyze them. If a particular topic proves to be troublesome, start with a clean slate again. Do not hesitate to go back to the basics if the mocks signal you to do so. Also, make sure that you are improving your question selection skills with each passing mock.