Your leaving Angels 33 point 5? Or Flight level 335..?

The 33 point 5 is what spawned the question. A new airline pilot
asked me what was proper instead of the 33.5 that most people seem to
use.

I didn't carry my decimals properly and missed the friggin obvious
answer.

Flight Level 335 is proper. Obviously, I don't fly those altitudes.
:-)

Thanks