Hey Rajendra.

Here is the Top 20 Percentile for the Jharkhand board for various different categories in 2018

General-  321

OBC- 332

SC- 310

ST- 306

PWD- 306

You can use the link below for more details.

https://www.google.co.in/amp/s/engineering.careers360.com/articles/top-20-percentile-cutoff-of-class-12-boards-for-iit-admission%3famp

Best of luck!