Example:
15 mile per US gallon = 6.377156e-12 Pm/L
1 mile per US gallon = 4.251437e-13 Pm/L | 1 Pm/L = 2.352146e+12 mile per US gallon
Conversion Steps:
15 × (425.1437075 / 1e+15) = 6.377156e-12