Question

A car starts with a dull tank of gas. After driving around 5he city, 1/7 of the gas has been used. With the rest of the gas in the car, the car can travel to and from Ottawa three times. What fractions of a tank of gas does each complete trip to Ottawa use?

Answer 1

`(2)/(7)`

Explanation:

Given:

A car starts with a dull tank of gas

1/7 of the gas has been used around the city.

With the rest of the gas in the car, the car can travel to and from Ottawa three times.

Question asked:

What fractions of a tank of gas does each complete trip to Ottawa use?

Solution:

Fuel used around the city =
`(1)/(7)`

Remaining fuel after driving around the city = 1 -
`(1)/(7)`

=
`(7 - 1)/(7) = (6)/(7)`

According to question:

As from the rest of the gas in the car that is
`(6)/(7)`, the car can complete 3 trip to Ottawa which means,

By unitary method:

The car can complete 3 trip by using =
`(6)/(7)` tank of gas.

The car can complete 1 trip by using =
`(6)/(7) / 3`

=
`(6)/(7) *(1)/(3)`

=
`(6)/(21)`

=
`(2)/(7)` tank of gas

Thus,
`(2)/(7)` tank of gas used for each complete trip to Ottawa.