The railway recruitment board applies the procedure of normalisation of marks to adjust the candidate score as exam is conducted in various shifts and with different difficulty level of questions to be asked in the examination. The following procedure is taken in to consieration while normalising the score. Here is the formula by which authority calculate the normalized marks for NTPC exams in the following entitled terms- Xn= (S2/S1) (X-Xav) + Yav Where Terms are Xn= Normalized Score of an Applicant S2= Standard Variation of Raw marks of Base Session S1= Standard Variation of Raw marks of Applicant Session X= Raw marks of the applicant which is to be normalized Xav= Average of Raw marks of Applicant Session Yav= Average of Raw marks of Base Session