Do you really mean scaled mark, or do you mean aligned mark?
An aligned mark of 80 in General is achieved by about the top 25% of the state.
80 is equivalent to an ATAR of about 75. What are you aiming for ATAR-wise?
If you really mean 'scaled', then that is achieved by about the top 7% of the state.
This would correspond with an ATAR of about 94.