Cutoff for B.Tech confirmation through Hpcet 2019 is 20% for General Category and 15% in Reserved class. This implies you need atleast 15% of 300 (absolute checks in hpcet) which is 45. So with 51 score in HPcet you are qualifed in the exam and are eligible for applying admission in government college. based on college hpcet marks cutoff and sc category seats available and cutoff you can get suitable college.

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