Hello Aspirant,

The calculation of the marks & rank would be difficult based on your percentile.

You may calculate your expected rank by this formula

100 - your total percentile score is the percentage  of people ahead of you. 874469 are the number of candidates appeared for Jan exam. So rank formula is (100 - your total score) X 869010 /100. If the number of candidates for April exam increased to 1200000 then your final rank shall be (100 - your total score) X 1200000/100

Using the formula
(100-your total percentile) X 869010/100

Your probable rank will be 1,82,492.

I would suggest you to appear for JEE Main April Session 2020 which application form is expected to start from 7th February, 2020. Try to score well in entrance Exam.

You can also use JEE Main college Predictor tool to know your admission possibilities in state level counselling.

Good Luck!