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? 
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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)
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Upstream: 6(s-c) = 90
Downstream: 3(s+c) = 90
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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 = {{{45/2}}}
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
{{{90/7.5}}} = 12 min to drift down stream, the same distance that he swam
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