Hey Pinki Devi,
As per your concern and rules by Indian government. Nearly 23 percent of seats are reserved for SC/STs combine. Whereas 27 % for the OBCs. and newly introduced 10% reservation to The EWS Category. So you can calculate the amount for seats across Bihar and get an total of 23 % of all. For an idea of available seats for SCs.
Best Of Luck
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