Yeah that is what I thought. I said about 700 just doing the math in my head but he said no...PAO2 = ( FiO2 * (Patm – PH2O)) – (PaCO2 / RQ).
It depends on certain factors. Are you at sea level? Do they have a normal resp quotient? What's the PACO2.
If you are to assume everything is "normal" with a PaCO2 of 40 then it would be ~663mmHg
He didn't follow that by telling you the answer and how he arrived at it?
That's some mighty fine teaching there, Lou.