if i obtain 80 marks in quantitative aptitude 80 marks in data interpection and 80 marks in verbal reasoning what is my total percentile of cat because my 10th and 12 marks is low ?
Your CAT percentile has nothing to do with class X and XII marks.
The percentile indicates your performance relative to the other candidates. For example if you get 80 percentile it means your score is more than 80% of the appearing students.
The percentipe is calculated as:
where R=Rank of student and N=Number of students who appeared.
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The CAT percentile is determined based on the no.of Candidates who appeared for the exam that year and the no.of students who scored lesser than you. Let's say your CAT sectional percentages are 80 i n all the 3 sections, then your overall percentage of approximately 85-90. But the percentile can be calculated only when we have the total no.of Candidates who appeared for the exam, no.of Candidates who qualified for the next round and also the no.of Candidates who scored less than you. So it is difficult to predict.