Hello Aman,
It is not compulsory to have maths in your +2 to be eligible to appear in CA and admissions to IIM. The minimum percentage requirement is of 50% in your bachelors degree.
However minimum percentage requirements do not guarantee a call from the institute. The shortlisting is based on various factors and weightage is given to your 10+2 and bachelors percentages along with other factors. Also, evert IIM has a separate method of shortlisting candidates.
For more details of the selection process please follow the link below :
https://bschool.careers360.com/articles/iim-admission-criteria/amp
Hope this helps.
All the best!
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