Question

Mr. fink's economy car can travel 420 miles on a 12 gallon tank on gas. Determine how many miles he can travel on 8 gallons

Answer 1

420 miles on 12 gallons
x miles on 8 gallons
420/x   = 12/8
use cross multiply

420*8 = 12*x
3840 = 12x
x = 3840/12
x=320

Answer 2

Answer: 280 miles.

Step-by-step explanation:

We know that the distance traveled by vehicle is proportional to the  gallons of gas in it.

Let x be the distance traveled in 8 gallons.

Given : Mr. fink's economy car can travel 420 miles on a 12 gallon tank on gas.

By proportionality , we have

$\dfrac{x}{8}=\dfrac{420}{12}\\\\\Rightarrow\ x=\dfrac{420}{12}\times8=280$

Hence, distance traveled in 8 gallons = 280 miles.