we've got that the x/760 is if you prescribe the letters to numbers i.e a=1 b=2 c=3 then they add to x if you dont include repeat letters
Apparently, the score you get is the sum of all the letters at the top, A=1, B=2, C=3 etc. That would explain why it's out of 780 (30 * 26=780)
That's for you to find out... BWWAAAAAAHHHHH *INCEPTION THEME PLAYS*