I don't know about WA, but in Victoria this is my understanding:
- In Year 11, the only thing that matters is that you pass.
- In year 12, the "ranking" matters more than individual scores.
- If your sac ranking matches your exam ranking, then all good, and your sac mark will be scaled according to ur exam mark. (This can make those atar predictors rather inaccurate, as your sac score is dependent on ur exam score. So if you got full marks, but 50% on the exam, then your SAC score will drop by heaps)
The general rule of thumb is:
- You don't want someone you will beat on the exam, getting above you in the rankings....
If you end up beating someone ranked above you, their score will be scaled up, and urs down. (I think)
There are many stories of people doing really really well at the end of the year, but their study score can drop like 5 study points because of their sac-marks (compared to others in their cohort).
Sorry to hear about your test. Don't worry, just keep working hard you'll do fine. It's good if its hard, so you are prepared for the exam!
Hope this helps