<PRE><B>Question 52500</B>

The above solution is not correct.
Here is the correct solution:


Using the formula t=s/v 

where t=time, s=distance, v=speed 

      12/(15+x)=9/(15-x) 


Solving for X, multiply both sides by (15-x)/(15+x) 


      12(15-x)=9(15+x) 


      180-12x=135+9x 


      180-135=12x+9x 


       45=21x 


       x=45/21=15/7 = 2 1/7


Then the speed of the current x=15/7 or 2 1/7 miles per hour.
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