Question

The distance traveled by a certain vehicle varies directly to the amount of fuel the vehicle consumes. The vehicle traveled 90 mile on 5 gallons of fuel. At the same rate, how far would the vehicle travel on 7 gallons of fuel

Answer 1

The vehicle covers 126 miles on 7 gallons of fuel.

Explanation:

Given:

The distance traveled is directly proportional to the amount of fuel.

For
`F` gallons of fuel distance traveled
`D` miles can be given as:

`D` ∝
`F`

`D=kF`

where
`k` is constant of proportionality.

The vehicle covers
`D=90` miles on
`F=5` gallons.

So

`90=k(5)`

Dividing both sides by 5.

`(90)/(5)=(k(5))/(5)`

`18=k`

∴
`k=18`

When
`F=7` gallons

`D=(18)(7)`

`D=126` miles

∴ The vehicle covers 126 miles on 7 gallons of fuel.