Not a burning topic, just one I've been thinking about my whole professional life and never thought to ask about. Maybe the answer is obvious, but it's eluded me thus far.
I only use digital incident meters, so this question isn't pertinent to some.

Let's say I have a lens of maximum aperture f/6.8 and I want to shoot at f/6.8.
My meter reads in whole stops, then in 1/10 f-stops, for example f/5.6 plus 3/10s, or as it's displayed: "5.67"

f/4.5 is easy to correlate on the meter, it's 4.05.
But I also have f/3.2, f/9, and f/6.3 to figure out. Is f/6.3 6/10 of a stop more than f/5.6? 9/10? I don't know.

Where would I find f6.8 to correspond with what the meter is capable of displaying? Where's f/6.8 on the meter?
Is there a scale somewhere that gives the equivalents to these odd maximum apertures?

TIA