SOLUTION: While canoeing on a river, your paddling speed is twice the river's current. You travel 3 miles downstream and then 3 miles upstream to get back to where you started. [ Write a rul

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Question 938248: While canoeing on a river, your paddling speed is twice the river's current. You travel 3 miles downstream and then 3 miles upstream to get back to where you started. [ Write a rule for T(s), the function that gives your total trip time (in hours) as a function of the current's speed s (in miles per hour). The rule should involve a sum of two rational expressions. Carry out the addition to simplify the expression as much as possible. ]
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+2s+%2B+s+ = speed going downstream
+2s+-+s+ = speed going upstream
----------------
Going downstream:
(1) +3+=+%28+2s+%2B+s+%29%2At%5B1%5D+
Going upstream:
(2) +3+=+%28+2s+-+s+%29%2At%5B2%5D+
---------------------
(1) +3+=+3s%2At%5B1%5D+
(2) +3+=+s%2At%5B2%5D+
------------------
(1) +t%5B1%5D+=+1%2Fs+
(2) +t%5B2%5D+=+3%2Fs+
-----------------
+t%5B1%5D+%2B+t%5B2%5D+=+1%2Fs+%2B+3%2Fs+
+T%28s%29+=+1%2Fs+%2B+3%2Fs+
+T%28s%29+=+4%2Fs+