Question

Carol's car average is 17.1 miles per gallon in City driving and 24.7 miles per gallon in highway driving if she drove a total of 513.0 miles on 26 gallons of gas how many of the gallons were used for City driving​

Answer 1

the volume of the gas used for city driving is 17 gallons

Explanation:

Given;

average speed for city driving, v₁ = 17.1 miles per gallon

average speed for highway driving, v₂ = 24.7 miles per gallon

total distance traveled, d = 513 miles

total gallon of gas used, t = 26 gallons

Let the volume of gas used for city driving = x

Also, let the volume used for highway driving = y

x + y = 26 -------- (1)

17.1x + 24.7y = 513 ------------(2)

From equation (1); y = 26 - x

Substitute the value of y in equation (2)

17.1x + 24.7(26-x) = 513

17.1x + 642.2 - 24.7x = 513

17.1x - 24.7x = 513 - 642.2

-7.6x = -129.2

x = 129.2/7.6

x = 17 gallons

Therefore, the volume of the gas used for city driving is 17 gallons