Chennai Mathematical Institute, Chennai
No, there is not any particular requirement in 12th board to get admission in CMI's Undergraduate Programs.
However one has to pass his/ her 12th Board Exams with sufficient marks and has to qualify its entrance exam (or ateast one of olympiads INMO, IMO, IPhO, etc.) to get admission.
For
You may already know that CMI is one of the best institutes in India to pursue Mathematics. CMI conducts an entrance exam each year for the students to get admission in the institute. You can get the entrance exam's question paper at Chennai Mathematical Institute's website i.e.,
https://www.cmi.ac.in/admissions/sample-qp/ugmath2019.pdf
Yes you can get admission in Nitte Meenakshi College with your rank but it is difficult, considering that ECE branch is a decently in-demand course, and your rank is pretty decent. You can try through the vacancy rounds which will get you a better chance of getting admission there. And
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