I scored 81% in 10th and 62% in 12th (science). Do I have a chance of making it to IIM AHMEDABAD?

IIM Ahmedabad or even the top IIMs have very strict rules and regulations regarding the admission process. They strictly adhere to these rules. As of now, there is a rule that the average result combining class 10th and 12th should be at least 80 percent (for Science Students) and 87 percent (for Commerce Students).

If you are a general category student then it is less likely that you will be selected. Even if you get 100 percentile in CAT, you will not be shortlisted because of these criteria. However, you have other alternatives such as FMS, MDI Gurgaon, SP Jain, etc. These are some of the popular B-Schools that select students based on their CAT scores.