how much maths you will need depends on:
a) where you do your degree - I'm at UTS and I from what I can understand we aren't that into the crazy maths aspect in first year. Don't get me wrong you do stats and finance which are no walk in the park, but I don't think they compare to some of the stuff you have to do at unsw or syd [in saying that though i am pretty good at maths, so that may be my point of view]
and
b) what majors you choose - obviously a finance or economics major will be much more maths intensive than say accounting and business law (and by that I mean harder maths instensive, where you will need to use your integration, calculus and logs ect)