document.write( "Question 305389: Solve the problem. When Mary's car's tire pressure is 30 pounds per square inch (psi), it averages 20.8 mpg of gasoline. If the tire pressure is increased to 35 psi, the car averages 21.6 mpg of gasoline. If Mary drives an average of 20,000 miles per year, how many gallons of gasoline will she save in one year by increasing her tire pressure from 30 psi to 35 psi (round to the nearest unit)? Show your step by step work! \n" ); document.write( "

Algebra.Com's Answer #218648 by josmiceli(19441) $\"\"$ $\"About$

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\n" ); document.write( "Just looking at the units and no numbers:
\n" ); document.write( "(miles driven) / (mi/gal) = gallons consumed
\n" ); document.write( "--------------------------------------------
\n" ); document.write( " $\"20000%2F21.6+=+925.926\"$ gallons consumed in a year
\n" ); document.write( " $\"20000%2F20.8+=+961.538\"$ gallons consumed in a year
\n" ); document.write( " $\"961.538+-+925.926+=+35.612\"$
\n" ); document.write( "She saves 36 gallons in a year by increasing tire pressure \n" ); document.write( "

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