+3 votes
in Mathematics by kratos

A man can row 28/3 km ph in still water and he finds that it takes him thrice as much time to row up than as to row down the same distance in the river. The speed of the current is:

a) 10/3 km/hr

b) 28/9 km/hr

c) 14/3 km/hr

d) 9/2 km/hr

1 Answer

+5 votes
by kratos
 
Best answer

Correct option: c) 14/3 km/hr

Explanation:

Let speed upstream be x km ph. Speed downstream = 3x km ph.

Speed in still water= 1/2*(3x+x)=2x km ph 2x=28/3 therefore x=14/3 km ph, speed downstream =14 km ph

Speed of the current= i/2*(14-14/3) =14/3 km ph

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