Question 520255: In a river with a steady current, it takes Cal Q. Leytor six minutes to swim a certain distance upstream, but it takes him only three minutes to swim back. How many minutes would it take him to float this same distance downstream?
Please help and thanks!
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! In a river with a steady current, it takes Cal Q. Leytor six minutes to swim a certain distance upstream, but it takes him only three minutes to swim back.
How many minutes would it take him to float this same distance downstream?
:
I makes it easier if we assign a distance to this problem, say 90 meters
Then we can find the speed of the swimmer (c) in still water, and the speed of the current (c)
;
Upstream: 6(s-c) = 90
Downstream: 3(s+c) = 90
:
Simplify, divide the 1st equation by 6, and the 2nd equation by 3, results:
s - c = 15
s + c = 30
-------------adding eliminates c, find s
2s = 45
s = 
s = 22.5 m/min swimmer speed in still water
Find c
22.5 + c = 30
c = 30 - 22.5
c = 7.5 is the speed of the current, this is your speed if you drift with the current.
Find the time to travel 90 meters
 = 12 min to drift down stream, the same distance that he swam
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