$29.5\; mg$ of an organic compound containing nitrogen was digested according to Kjeldahl’s method and the evolved ammonia was absorbed in $20\; mL$ of $0.1\; M\; HCl$ solution. The excess of the acid required $15\; mL$ of $0.1\; M \;NaOH$ solution for complete neutralization. The percentage of nitrogen in the compound is
