Hi

With 50 marks in Maths i. e 50 % in maths you are not eligible for BITSAT.

This is because,

To be eligible you need  at least 60 % separately in each of maths, physics, & chemistry.

Moreover ,

with your mentioned marks, your PCM aggregate % is less than 75 % i. e your PCM% is only 62 % with your mentioned marks and thus not eligible.

For your reference,

BITSAT 2022 examination eligibility criteria is given below:-

To be eligible  BITSAT 2022 examination ,

-------------) you should be either appearing for 12th board examination 2022 or should have passed it in 2021 with PCM i. e physics chemistry and mathematics  (or PCB i. e physics ,chemistry and biology in case of students applying for B Pharma, PCM candidates are also eligible for B Pharma)

-------------) You should have got at least 75% marks in aggregate of physics chemistry  and mathematics ( if you have taken mathematics for your BITSAT examination)  in 12th

or

at least 75% marks in aggregate of physics chemistry  and biology( if you have taken biology for your BITSAT examination)  in 12th

-------------) you must have got at least 60% marks individually in each of physics, chemistry  Maths/ biology  in 12th

-------------) There's no age limit to be eligible

You can check detailed information regarding eligibility at

https://engineering.careers360.com/articles/bitsat-eligibility-criteria/amp

Thankyou