Question 385891: A boat'screw rowed 20 miles downstream, with the current, in 2 hours. The return upstream, against the current, covered the same distance, but took 5 hours. Find the crew's rowing rate in still water and the rate of the current.
The crew's rowing rate is still water is ____ mile(s) per hour.
The rate of the current is ____ mile(s) per hour.
Answer by mananth(16946)   (Show Source):
You can put this solution on YOUR website! A boat'screw rowed 20 miles downstream, with the current, in 2 hours. The return upstream, against the current, covered the same distance, but took 5 hours. Find the crew's rowing rate in still water and the rate of the current.
The crew's rowing rate is still water is ____ mile(s) per hour.
The rate of the current is ____ mile(s) per hour.
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boat rate in still water = x
current rate = y
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Rate
upstream = x-y
downstream = x+y
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time downstream = time upstream
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t=d/r
20/(x+y)=2
multiply by (x+y)
20=2(x+y)
/2
10=x+y
x+y=10.................1
..
20/(x-y)=5
20=5(x-y)
/5
4=x-y
x-y =4..................2
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add 1 & 2
2x=14
/2
 mph boat rate in still water.
 mph rate of current
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m.ananth@hotmail.ca
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