SOLUTION: Carole's car averages 12.8 miles per gallon in city driving and 21.6 miles per gallon in highway driving. If she drove a total of 308.8 miles on 20 gallons of gas, how much of the

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: Carole's car averages 12.8 miles per gallon in city driving and 21.6 miles per gallon in highway driving. If she drove a total of 308.8 miles on 20 gallons of gas, how much of the       Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 1152022: Carole's car averages 12.8 miles per gallon in city driving and 21.6 miles per gallon in highway driving. If she drove a total of 308.8 miles on 20 gallons of gas, how much of the gas (to the nearest gallon) was used for city driving
Answer by josgarithmetic(39616) About Me  (Show Source):
You can put this solution on YOUR website!
R, fuel efficiency
V, volume of fuel, gallons
D, distance in miles
R=V%2FD

Question asks for how many gallons used in the city. Let this quantity be v. 
                  FUEL EFFC      VOL        DISTANCE
CITY              12.8            v         12.8v
HIGHWAY           21.6           20-v       21.6(20-v)
TOTAL                            20        308.8

12.8v%2B21.6%2820-v%29=308.8
.
.
steps
.
highlight%28v=14%29