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!
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