"Margin of error" for gas mileage is comical.From Fuelly.com:
"Based on data from 32 vehicles, 185 fuel-ups and 49,707 miles of driving, the 2017 Honda Ridgeline gets a combined Avg MPG of 21.13 with a 0.55 MPG margin of error."
Incidentally, that's not US MPG (rather British imperial).
You are currently converting fuel consumption units from litre per 100 kilometers to mile per gallon(US)
8.51 l/100km = 27.639786521739 mpg