TheNona wrote:

Can any body elborate more , please ? Thanks in advance

Let the speed in still water be x

Speed of stream = 3

So

Speed while going downstream = x+3

Time while going downstream = 3

Speed while going upstream = x-3

Time while going upstream = 4

Since distance traveled through both ways is same and time ratio being \(\frac{3}{4}\), the speed ratio must be \(\frac{4}{3}\)

\(\frac{Speed downstream}{Speed upstream}\) = \(\frac{4}{3}\)

\(\frac{x+3}{x-3}\) = \(\frac{4}{3}\) ------> 3x + 9 = 4x - 12 ----------> x=21

Speed in still water = 21

Distance = Speed X Time

Distance = (x+3)3 = 24 X 3 = 72

or

Distance = (x-3)4 = 18 X 4 = 72

Regards,

Narenn

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