SOLUTION: Bonnie's truck uses 8.9 L of gas for 100 km of city driving and 7.2 L for 100 km is of 100km of highway driving how many US gallons with the truck use in each case if She 50 Km in

Algebra ->  Length-and-distance -> SOLUTION: Bonnie's truck uses 8.9 L of gas for 100 km of city driving and 7.2 L for 100 km is of 100km of highway driving how many US gallons with the truck use in each case if She 50 Km in      Log On


   

Question 1008882: Bonnie's truck uses 8.9 L of gas for 100 km of city driving and 7.2 L for 100 km is of 100km of highway driving how many US gallons with the truck use in each case if She 50 Km in the city into and 250km on the highway
Answer by josgarithmetic(39626) About Me  (Show Source):
You can put this solution on YOUR website!
Manage volume units later. First, analyze and solve the main problem.
This is a fuel efficiency uniform rates problem 

         RATE         VOLUME       DISTANCE
         km/L          Liters      Kilometers
CITY       C           8.9          100
HWY        H           7.2          100


Find rates, C and H.
C=100%2F8.9=1000%2F89
and
H=1000%2F72

How much fuel used, first as liters, for 50 km "into" the city and 250 km on highway? (Assuming the combination, addition).

R*V=D rate volume distance
V=D/R to find volume

50%2F%281000%2F89%29%2B250%2F%281000%2F72%29, in LITERS
50%2889%2F1000%29%2B250%2872%2F1000%29
5%2A89%2F100%2B25%2A72%2F100
%285%2A89%2B25%2A72%29%2F100
2245%2F100
highlight%28449%2F20%29, LITERS



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3.7854 Liters is 1 US Gallon.