Question 1017670
In words:
[ miles / hr ] / [ miles / gallon = [ gallons / hr ]
{{{ 40 / 20 = 2 }}} gallons / hr
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Now you have to do:
[ gallons / hr ] x [ hrs driven ] = [ gallons used ]
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Then do a unit conversion:
[ gallons ] x [ liters / gallon ] = [ liters used ]