CSSE Standardised score calculation:

Say if a child gets 40 marks in English and 40 marks in Maths then standardised score is 321.193566

English Marks       Eng Avg             Eng SD

40                         33.174               8.665

Maths Marks        Maths Avg         Maths SD

40                         38.349              10.709

Eng Std              Maths Std

111.8165032       102.3125409

TotalMarks         CSSE Score

80                       321.193566

English Std score =((40-33.174)/8.665*15)+100 = 111.8165032

Maths Std score =((40-38.349)/10.709*15)+100 = 102.3125409

Total Score = =1.5*(111.8165032+102.3125409 ) = 321.193566

 

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