Generally you require minimum 50% in your Graduation to get admission in a decent college for Managemnet programme, If you have less than 50% then you will not be eligible to apply for CAT, CMAT etc. as a General category. You can apply for XAT & MAT Entrance Exam but the Colleges which you will get mostly won't be of good reputation and getting a MBA degree might not be worth it. But still if you are really interested in pursuing MBA degree then give MAT & XAT exams & try to get a very high percentile then you might have a chance of ending up in an average college.

Good Luck!