<PRE><B>Question 319228</B>
THE SPEED OF A BOAT IN STILL WATER IS 8 KM/HR.
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IF HE TAKES SAME TIME IN GOING 20 KM DOWNSTREAM AS IT TAKES
IN GOING 12 KM UPSTREAM,FIND THE SPEED OF RIVER?
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Downstream DATA:
distance = 20 km ; rate = c+8 kph ; time = 20/(c+8) hrs.
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Upstream DATA:
distance = 12 km ; rate = c-8 kph ; time = 12/(c-8) hrs
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Equation: 
20/(c+8) = 12/(c-8)
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20(c-8) = 12(c+8)
20c-160 = 12c + 96
8c = 256
c = 32 kph (speed of the current)
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Cheers,
Stan H.
</PRE>