I have a 78.4% in my 11th grade and 63.2% in my midterms.
Despite that I got accepted into PURDUE for FYE and RIT with 18k scholarship.
As far as I know, some of these top schools don’t place emphasis on CBSE internal examinations.
For eg: UIUC only asked me my 10th CBSE results and nothing else. No 9th grade CGPA, no 11th grade marks or 12th grade midterm results.
** So, you just have to take the extra effort, email every prospective college and just ask, whether they give weight-age to it or not. And if they do, what is considered as a good percentage. **
One cannot compare the CBSE grading system to the American, IGCSE or IB board. This is because in our internal markings, the teacher correct our papers strictly, often taking the marks we deserve so that we are motivated to score more in the boards.
And considering the number of applicants from India, I am pretty sure most of the admission officers do know that.