Question 201288: A fish swim 8 miles downstream in two hours. he return upstream in 14 hours. how fast does the fish swim in still water ? Found 2 solutions by Alan3354, josmiceli:Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website! A fish swim 8 miles downstream in two hours. he return upstream in 14 hours. how fast does the fish swim in still water ?
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c = speed of the current
r = speed of the fish
use d = rt
8 = (r+c)*2 downstream
8 = (r-c)*14 upstream
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2r + 2c = 8 --> 14r + 14c = 56
14r-14c = 8
14r+14c = 56
------------- Add the equations
28r = 64
r = 16/7 mph
You can put this solution on YOUR website! Let = fish's speed in still water in mi/hr
Let = speed of current in mi/hr
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Given: hrs = time to go mi downstream hrs = time to go mi upstream
------------ mi mi
and
(1)
(2)
Multiply both sides of (1) by and
add the equations
(1)
(2) mi/hr answer
check answer: mi/hr
and close enough
