SOLUTION: Julie and Eric row their boat (at a constant speed) 40 miles downstream for 4 hours, helped by the current. Rowing at the same rate, the trip back against the current takes 10 hour

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: Julie and Eric row their boat (at a constant speed) 40 miles downstream for 4 hours, helped by the current. Rowing at the same rate, the trip back against the current takes 10 hour      Log On


   

Question 99644: Julie and Eric row their boat (at a constant speed) 40 miles downstream for 4 hours, helped by the current. Rowing at the same rate, the trip back against the current takes 10 hours. What is rate of the current? What is the rate that Julie and Eric row?
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
40=4(s+c) or 40=4*10 or (s+c)=10
40=10(s-c) or 40=10*4 or (s-c)=4
(s+c)=10
(s-c)=4 now add
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2s=14
s=14/7
s=7 speed of the boat
7+c=10
c=10-7
c=3 speed of the current.