Question 913195
Chad paddles 55m/minute in still water. He paddles 150 m upstream and 150 m downstream in a total time of 5.5 minutes. What is the speed of the current?
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let c=speed of current
55+c=speed of boat downstream
55-c=speed of boat upstream
travel time=speed/distance
..
{{{150/(55+c)+150/(55-c)=5.5}}}
lcd:(55+c)(55-c)
150(55-c)+150(55+c)=5.5(55+c)(55-c)
150*55-150c+150*55+150c=5.5(55^2-c^2)
16500=16637.5-5.5c^2
5.5c^2=137.5
c^2=25
c=±√25
c=5
speed of the current=5 m/min