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A man can row 36 km/hr in still water. It takes him thrice as long to row up as to row down the river. Find the rate of stream.
- A18 km/hr
- B5 km/hr
- C8 km/hr
- D10 km/hr
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CCommunity
Let the rate of stream be x km/hr
Let the length of the river be y km.
Time taken to row up = y/(36 - x)
Time taken to row down = y/(36 + x)
y/(36 - x) = 3y/(36 + x)
⇒ 36 + x = 108 – 3x
⇒ 4x = 72
⇒ x = 18 km/hr
Let the length of the river be y km.
Time taken to row up = y/(36 - x)
Time taken to row down = y/(36 + x)
y/(36 - x) = 3y/(36 + x)
⇒ 36 + x = 108 – 3x
⇒ 4x = 72
⇒ x = 18 km/hr