First let us go through the percentile system and marking scheme of CAT exam. In total there are 100 questions and each carry 3 marks. For every wrong answer one mark is deducted from the total score. In case of non-MCQ questions, there is no negative marking.
Now students due to appear for the exam already know that they do not need to attempt all the questions in order to be in the top 99-100 percentile. Last year one of the 100 percentile scorer, Yash Choudhari from Pune scored 86.15 in VRC, 60.44 in DI and LR and 73.50 in QA as scaled scores.
This brings us to the concept of normalization of scores. Every year the scores of students who appear for CAT exam are normalized. Normalization is done to put all candidates, irrespective of their academic background, location, and other such defining factors, on a level ground. Normalization is also followed to eliminate any disadvantage a student may have if the questions differ in difficulty level in the different sessions of the exam.
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For example, IIM Ahmedabad, when shortlisting candidates for WAT and PI, considers the following factors:
- Percentage in 10th class exam
- Percentage in 12th class exam (separate weightage for the different streams)
- Percentage in Bachelor's examination
Other IIMs may follow similar selection criteria or may have one or more additional shortlisting criteria which includes stream of education at degree level, and gender diversity.
Last year, Vidit Garg made it to IIM Ahmedabad with a percentile score of 89.67 in CAT 2016. This goes on to show that just percentile score is not enough to get a call from IIMs.
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