What's the average of 5 MPG and 10 MPG?
The math isn't quite obvious to me, but if you go out camping and get 5 MPG on the way to the campground and turn around and get 10 MGP on the way back, your average MPG won't be 7.5 as you would expe...
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Thanks - I officially blame the phone! :)
Correct. However, I think for most people, in this setting, the "average mpg" and the "combined mpg" would be used interchangeably to refer to the same number - the actual mpg for the combined trips.
The confusion is that people think the average and the harmonic mean will provide them with the combined MPG. However, the average will only fit if the gallons used are the same; the harmonic mean will only fit if the distance driven is the same. If the gallons used and distance driven are both different, then those calculations cannot be used as a "shortcut" to determine combined mpg.
Correct. However, I think for most people, in this setting, the "average mpg" and the "combined mpg" would be used interchangeably to refer to the same number - the actual mpg for the combined trips.
The confusion is that people think the average and the harmonic mean will provide them with the combined MPG. However, the average will only fit if the gallons used are the same; the harmonic mean will only fit if the distance driven is the same. If the gallons used and distance driven are both different, then those calculations cannot be used as a "shortcut" to determine combined mpg.
