SOLUTION: Carole's car averages 13.4 miles per gallon in city driving and 25.7 miles per gallon in highway driving. If she drove a total of 522.8 miles on 28 gallons of gas, then how many of
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-> SOLUTION: Carole's car averages 13.4 miles per gallon in city driving and 25.7 miles per gallon in highway driving. If she drove a total of 522.8 miles on 28 gallons of gas, then how many of
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Question 230685: Carole's car averages 13.4 miles per gallon in city driving and 25.7 miles per gallon in highway driving. If she drove a total of 522.8 miles on 28 gallons of gas, then how many of the gallons were used for city driving? Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! Let = miles of hwy driving
Let = miles of city driving
given:
Total gas used = 28 gallons
(1)
(2)
This is 2 equations with 2 unknowns, so
it's solvable
(1)
Multiply both sides by
(1)
(1)
Multiply both sides of (2) by
and subtract from (1)
(1)
(2)
214.4 gallons were used for city driving
check answer:
and
OK
