SOLUTION: A crew times itself on a three-mile course. The three miles upstream takes 20 minutes, and the three miles downstream takes 12 minutes. Find the rate of the crew in still water.
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Question 901434: A crew times itself on a three-mile course. The three miles upstream takes 20 minutes, and the three miles downstream takes 12 minutes. Find the rate of the crew in still water. Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! A crew times itself on a three-mile course. The three miles upstream takes 20 minutes, and the three miles downstream takes 12 minutes. Find the rate of the crew in still water.
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let x=rate in still water
let c=rate of current
x+c=rate of crew downstream
x-c=rate of crew upstream
distance/speed=travel time
..
12 min=1/5 hr
20 min=1/3 hr
x+c=15
x-c=9
add
2x=24
x=12
c=x-9
c=3
rate in still water=12 mph
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