simple query to add 10 business days to date:

SELECT tmp.release_date, tmp.num
  FROM (    SELECT TO_DATE (SYSDATE + LEVEL, 'DD-MON-RRRR') release_date,
                   TO_CHAR (SYSDATE + LEVEL, 'DY') day, rownum num
              FROM DUAL
             WHERE TO_CHAR (SYSDATE + LEVEL, 'DY') NOT IN ('SAT', 'SUN')
        CONNECT BY LEVEL < 15) tmp
        where tmp.num = 10