The result of your conversion between miles/gallon(US) and gigajoule appears here
To convert between Miles/gallon(US) and Gigajoule you have to do the following:
First divide 5 / 1.0e+09 = 0.00000001
Then multiply the amount of Miles/gallon(US) you want to convert to Gigajoule, use the chart below to guide you.
Symbol: m/G
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Symbol: GJ
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