Example:
15 Pm/L = 4.237214e+13 mile per UK gallon
1 Pm/L = 2.824809e+12 mile per UK gallon | 1 mile per UK gallon = 3.540062e-13 Pm/L
Conversion Steps:
15 × (1e+15 / 354.00619) = 4.237214e+13