mozart, from ur description, u'll do perfectly fine, with ur kinda dedication atm, ur definitely not looking at 87 if you live up to your promises, i say 95+
if u have this "need" to understand mathematics, that just proves your ability to do maths
from this year's 3/4 exam, however, to get an awesome score not only do you need to understand the material, you also need to be able to recognise the problem you're presented with and be able to apply things you have learnt to solve it. If you can use your "understanding" to solve problems without specific instructions, then you're looking at WELL above your predicted 35...
but on the higher end, also note that every little mistake is your enemy, so practice at it
dont overstress, you're in year 11, there's no point getting yourself worked up right now, enjoy your holidays, coz you dont have many left...
ENJOY

you'll do fine
which 1s set notation, worded problems?
set notation as in [0,5) or {0,1,2,3,4} or f: [0,5) -> R... and those kinda stuff... dont worry about it, you'll learn it easy enough, just remember what each bracket mean, and if you REALLY need to, draw the number line....
