Question 1182603
.
A commuter plane flew to a small town from a major airport. 
The plane's average speed flying to the small town was 250 mph, and its average speed 
returning to the major airport was 150 mph. The total flying time was 4 hours. 
Find the distance between the two airports.
~~~~~~~~~~~~~~~


<pre>
Let d be one-way distance.


Time to flight to there is  {{{d/250}}}  hours.


Time to flight back is  {{{d/150}}}  hours.


Total time equation is


    {{{d/250}}} + {{{d/150}}} = 4  hours.



The setup is done.

Now our task is to solve it.



Multiply both sides by 750. You will get


    3d + 5d = 3000

      8d    = 3000

        d   = 3000/8 = 375 miles.


<U>ANSWER</U>.  One way distance is 375 miles.


<U>CHECK</U>.  {{{375/250}}} + {{{375/150}}} = 1.5 hours + 2.5 hours = 4 hours.    ! Correct !
</pre>

Solved and explained in all details.