I don't know it very well~~ I took 30-25-55 twice, it means you grammar full score is 13, essay is 17, first time , my grammar is 9, twe(type in computer) is 5.0, so I got grammar/essay 25 second, my grammar is 13, twe (by hand write) is 5.0, So I got grammar/essay is 28, I don't know how to decide the score, keep relax, good luck