Hello Roshan,

KEAM score is calculated in a 50:50 ratio based on both the entrance marks and board marks the aggregate result is calculated. It doesn't mean that you need 50% marks in KEAM as compulsory, it only means that whatever you score in KEAM will contribute 50% in the preparation for the rank list.

The score obtained by the candidate in the Engineering Entrance Examination (Paper I & Paper II put together) is computed out of 300, and added to the total standardized marks of Mathematics, Physics and Chemistry/Computer Science/Biotechnology/Biology as the case may be, of the final year of the Qualifying Examination, computed out of 300, both corrected to four places of decimals.

For 12th, you do need 50% marks in Mathematics separately, and 50 % marks in Mathematics, Physics and Chemistry put together to be eligible for admission. 

Hope this answers your query, feel free to ask for more info.