<PRE><B>Question 756486</B>
I am answering this assuming that while coming back it is downsteam 
Suppose rowing speed is x km/hr 
Flow of stream is 2km / hr

  1/x-2 + 1/x+2 =72 

  x+2+x-2=72(x+2) (x-2)   [taking LCM]

 x+x= 72 (x^2-2x+2x-4) 

2x=72 (x^2+4) 

2x= 72x^2-288

0 = 72x^2-2x-288

0 = 2 [36x^2-x-144] 

hay it is half of the way accoding to me solution shld be like this do u hv answer for this i think there may be mistake inb question plz recheck the question and tell me if q is perfect tell me answer i will solve further for u thanks

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