Hello student you can't judge someone on the basis of marks obtained in class 12 as there are many students who didn't score good in class 12 but they're clearing all the stage of CA in first attempt. Chartered accountants is a course which need your persistency no matter if you're topper or not if you can study for 10-12 Hrs daily then you can clear the examination. Yes one who top Accountancy In class 11-12, things are little easy for them as they can grasp very easily but it's not like they can easily do all the things as syllabus is very lengthy.

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Good luck