<PRE><B>Question 934655</B>
Two canoeists paddle 10km upstream in 5 hours. They make the return trip in only 1 hour. Assuming that the canoeists paddle at a constant rate, what is the speed of the current?
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let x=speed of canoe in still water
let c=speed of current
(x+c) speed of canoe downstream
(x-c) speed of canoe upstream
travel time*speed=distance
..
5(x-c)=10
1(x+c)=10
..
5x-5c=10
x+c=10
..
5x-5c=10
5x+5c=50 (mult. eq. by 5)
subtract
10c=40
c=4
speed of current=4 km/hr</PRE>