Question 433975
.
A long distance runner started on a course running at an average speed of 6 mph. 
one-half hour later, a second runner began the same course at an average speed of 7mph. 
How long after the second runner started did the second runner overtake the first runner?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~



        As I read the solution in the post by @mananth, it makes me laugh.

        The runners are confused with trains, and the input numbers are confused with other, irrelevant numbers.

        The solution and the answer in the post by @mananth both are incorrect.

        So,  I came to bring a correct normal solution.



<pre>
Runner I	6	mph
Runner II	7	mph

							
Difference in time =	1/2 of an hour				
Runner I will have covered 3 miles before Runner II starts

							
catch up distance=		3	miles				
catch up speed =		7-6	mph			
catch up speed =		1	mph				

							
Catchup time = catchup distance/catch up speed							
catch up time=		3/1			
catch up time=		3 hours	    <<<---===  <U>ANSWER</U>
</pre>

Solved correctly.