see i think they divide ur snap score by 2 to get out of 100. now they give u marks for ur past performance... eg. i got 46 in snap, so i got 23 in sicsr. now i got further 17/20 for my past performance, so i got 40/120.
now they will do gd=40 marks and pi=40 marks... hope u got it...
regards,
linuxfreak