SOLUTION: Julio has found that his new car gets 36 miles per gallon on the highway, and 31 miles per gallon in the city. He recently drove 397 miles on 12 gallons of gas. How many highway mi

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Julio has found that his new car gets 36 miles per gallon on the highway, and 31 miles per gallon in the city. He recently drove 397 miles on 12 gallons of gas. How many highway mi      Log On


   



Question 390074: Julio has found that his new car gets 36 miles per gallon on the highway, and 31 miles per gallon in the city. He recently drove 397 miles on 12 gallons of gas. How many highway miles did he drive? How many city miles did he drive?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Julio has found that his new car gets 36 miles per gallon on the highway, and 31 miles per gallon in the city. He recently drove 397 miles on 12 gallons of gas. How many highway miles did he drive? How many city miles did he drive?
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Equation:
distance + distance = distance
36x + 31(12-x) = 397
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36x + 31*12 - 31x = 397
5x = 25
x = 5 gallons (amt. used in highway driving)
5*36 = 180 miles of highway driving
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12-x = 7 gallons (amt. used in city driving)
31*7 = 217 miles of city driving
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Cheers,
Stan H.