Question 1171125
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<pre>

Let d be the distance from the starting point to the overtaking point 
(exactly the unknown value under the question).


For the first train, the travel time is  {{{d/30}}}  hours.

For the second train, the travel time is  {{{d/45}}}  hours.


The difference is 2 hours, according to the condition


    {{{d/30}}} - {{{d/45}}} = 2  hours.


You got your basic equation to find the unknown distance d.


To solve the equation, multiply both sides by 90.  You will get


    3d - 2d = 180

       d    = 180.


<U>ANSWER</U>.  The overtaking point is in 180 miles from the station X.
</pre>

Solved.