Hi vaihavjindal85, I'm assuming you referring to National University of Singapore (NUS) and Nanyang Technological University (NTU).
What are your objectives for taking up an MBA? What type of MBA are you looking for? What format of studies are you looking to enroll in - full time (where you have to leave your job), part time (balancing work and studies tgt).
The recommended GMAT score for both NUS and Nanyang MBA program is 600 and above. A rich working experience with noteworthy career achievements will also help your chances in getting into these schools.
If you're looking to get into the tops business schools in Singapore, here's a link that you might find helpful - http://www.coursesinsg.com/2012/06/top-mbas-in-singapore.html
Let me know your thoughts