Welcome to MSO. Since UWA sets minimum ATAR 99.0 you will need to do better than predicted or have done a LOTE (to get a small ATAR bonus) or see if you qualify for the Broadway pathway. If you meet this condition 97 UMAT will get an interview and a fair chance for a place offer.
For Curtin the lowest ATAR depends on your UMAT as the two scores work in combination. I copy/paste from this post the known successful applicants last year
Med Place Offers 2017 - Collated Data by LMG
Curtin University
99.50, 98%, non-rural, unbonded
98.60, 98%, non-rural, unbonded
99.15, 96%, non-rural, unbonded
99.55, 96%, non-rural, unbonded
99.40, 84%, non-rural, unbonded
99.60, 92%, non-rural, unknown re. bonded/unbonded
99.30, 83%, non-rural, unknown
99.85, 84%, non-rural, unknown
99.25, 87%, non-rural, unknown
98.70, 83%, non-rural (although it could be via the Equity-school scheme - A1)