Question 850822
( miles ) / ( mi/hr ) = hrs driven
{{{ 40 / 40 = 1 }}} hr
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( miles ) / ( miles/gallon ) = gallons
{{{ 40 / 30 = 1.333 }}} gal used
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{{{ 8 - 1.333 = 6.667 }}} gal 
6.667 gallons leaked in 1 hr