On 07/21/2017 6:30 PM, Mad Roger wrote:
....

Am I correct to understand that you are saying if you go only 300 miles on
one tank, then the fill-level inaccuracy is (say) plus or minus 1 gallon
per tank; but if you go 3,000 miles (obviously on multiple tanks), that the
fill-level inaccuracy is one tenth of that plus or minus one gallon per
tank?

No, but the 1 gal error in the ~10X gallons _TOTAL_ over the 3000 mi is
only 1/10th of the (approx) tenth of that on each individual tank.

And it's only the total that matters in the overall average mileage...it
didn't matter on the intermediary tanks at all; they could be top-offs,
half-fills, full-fills; totally immaterial. All that matters is the
consistency in that last fill being to the same level as the first and
that one discrepancy is the only "error" that exists in that portion of
the total process...all the rest cancel identically.

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