Yes 50% is required for applying for cat

The minimum percentage of aggregate marks or equivalent CGPA to be obtained or secured by the applicants is 50 for General category candidates and 45 for reserved category candidates. So you can apply but you need to score good in CAT to get admission in Tier 1 colleges. For further you can go through with given below link.

CAT 2017

Common Admission Test

Eligibility | Application | Exam Pattern | Admit Card | Preparation Tips | Result | Answer Key | Accepting Colleges

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