SOLUTION: A canoeist can paddle 20.0 mi down a certain river and back in 8.0 h (40.0 mi round trip). She can also paddle 5.0 mi down river in the same time as she paddles 3.0 mi up river.

Question 834390: A canoeist can paddle 20.0 mi down a certain river and back in 8.0 h (40.0 mi
round trip). She can also paddle 5.0 mi down river in the same time as she
paddles 3.0 mi up river. Find her rate in still water, and ﬁnd the rate of the
current.
Answer by richwmiller(17219) (Show Source): You can put this solution on YOUR website!
r*t=d
t=d/r
a+b=8,
a*(x+c))+b*(x-c)=40,
a*(x+c))=b*(x-c),
5/(c+x)=3/(x-c)
a = 3, b = 5, c = 4/3, x = 16/3
speed in still water 16/3
current speed 4/3

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