Example:
15 J = 2.34996e-9 fuel oil equivalent @ barrel (US)
1 J = 1.56664e-10 fuel oil equivalent @ barrel (US) | 1 fuel oil equivalent @ barrel (US) = 6.383088e+9 J
Conversion Steps:
15 × (1 / 6.383088e+9) = 2.34996e-9