SOLUTION: A boat takes 3 hours To go 24 miles upstream. It can go 36 miles downstream in the same time. Find the rate of the current and the rate of the boat in still water if x = the rate o

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: A boat takes 3 hours To go 24 miles upstream. It can go 36 miles downstream in the same time. Find the rate of the current and the rate of the boat in still water if x = the rate o      Log On

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Question 796173: A boat takes 3 hours To go 24 miles upstream. It can go 36 miles downstream in the same time. Find the rate of the current and the rate of the boat in still water if x = the rate of the boat in still water and y = the rate of the current.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Going upstream:
(1) +24+=+%28+x+-+y+%29%2A3+
Going downstream:
(2) +36+=+%28+x+%2B+y+%29%2A3+
----------------------------
(1) +3x+-+3y+=+24+
(1) +x+-+y+=+8+
and
(2) +3x+%2B+3y+=+36+
(2) +x+%2B+y+=+12+
add the equations
+2x+=+20+
+x+=+10+
and
(2) +x+%2B+y+=+12+
(2) +y+=+2+
The current is 2 mi/hr
The rate in still water is 10 mi/hr