Formula
One tank's range is economy times its gallons. The fill-ups round up:
fill-ups = distance / (MPG × tank gallons)
The count rounds up to a whole fill-up. The trip fuel page adds a reserve percent and does not know the tank size. This page does.
Assumptions
- The tank is usable down to the gallons you enter.
- Economy stays constant.
- The price is per US gallon.
Worked example
900 miles at 30 mpg with a 12 gallon tank takes 3 fill-ups.
Input definitions
- Tank size
- Usable gallons between fill-ups.
- Fill-ups
- How many of those tanks the distance needs, rounded up.
Limitations
This is a trip sketch. Prices and rates are numbers you type. The currency control changes the symbol only and does not convert one currency into another.
Questions
Why round up?
A fraction of a tank still means another stop if you start full and do not want to arrive empty beyond that fraction.
What is the reserve page?
The trip fuel page increases the volume by a percent. It does not count tanks.