Is that through the country without traffic lights?He would consider himself having ridden 2.7 miles/day because rest days don't count against the average.
He's yelled at people in the past for their "idiot math" of averaging the zeroes into his daily mileage.
There are charity one-day rides that go 50 or 100 miles.
Most out of shape people not dragging a fucking heavy trailer behind them could probably go 10 mph. The dedicated weekend warriors can go 20-22 mph, and some really good riders are around 25-28 mph.