So the Mobil pump was a little faster and I put in 11.160 gallons there, making for a total gas input of 11.201 gallons for the 438.4 miles I had gone. And thus, my fuel economy turned out to be 39.14 miles per gallon.
I'm pleased with this result, because several of my commutes on this tank were following tractor trailers at unreasonably high speeds, for me anyway, of 70 to 75 miles per hour. So drafting at high speeds seems to result in fuel economies similar to driving granny style in the slow lane.
Meanwhile, I am driving to and from work every day this week and haven't ridden my bike any more. I hope to change that today and go out for a "healthy wellness ride" after lunch. And hopefully manage a couple good rides over the weekend. Then next week's a four-day week and a four-day weekend.