[Vwdiesel] Quantum Mileage

[Mark Shepherd]

Just went on a 100 mile trip to London and I decided to
check my mpg...
I had already travelled some 400 miles since the last
tank-fill around my town.
.
Total miles travelled 512.
Litres used:49.9
Av economy is (512/49.9) x 4.54 = 46.67mpg

This is how I worked out my interstate driving economy 'X'

Pure town driving I usually average 43mpg IMP
Town driving..... 404 miles
Distance driving 108 miles

[(404 x 43) + (108 x X)]/512 = 46.67

17372 + 108X = 23895

X =(23895-17372)/108

X=60.39mpg

This is comparable with my last long trip where I averaged
60.24mpg (50mpg US)

It's good to see my car still reasonably economic even
though I feel my compression may be weak and  I'm using some
oil maybe a quart every 500miles although some is oozing out
[for at least 2 years!] from behind a pulley.
I suspect the intermediate seal :o(
Can anyone shoot my math[s] down?

Mathematical-Miser