SOLUTION: A boat leaves Pt A and travels up-river for 3 hours to Pt B. On the return trip, it only takes 2 hours. If the boat travels at the same constant speed relative to the current, ho

Algebra ->  Customizable Word Problem Solvers  -> Travel -> SOLUTION: A boat leaves Pt A and travels up-river for 3 hours to Pt B. On the return trip, it only takes 2 hours. If the boat travels at the same constant speed relative to the current, ho      Log On

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Question 755356: A boat leaves Pt A and travels up-river for 3 hours to Pt B. On the return trip, it only takes 2 hours. If the boat travels at the same constant speed relative to the current, how far away is it between the two points?
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +c+ = the speed of the current
Let +s+ = the speed of the boat in still water
Let +d+ = the distance between A and B
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Boat going upriver:
+d+=+%28+s+-+c+%29%2A3+
Boat going downriver:
+d+=+%28+s+%2B+c+%29%2A2+
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By substitution:
+%28+s-c+%29%2A3+=+%28+s%2Bc+%29%2A2+
+3s+-+3c+=+2s+%2B+2c+
+s+=+5c+
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Using substitution again:
+d+=+%28+5c+-+c+%29%2A3+
+d+=+12c+
and, also
+d+=+%28+5c+%2B+c+%29%2A2+
+d+=+12c+
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12 times the speed of the current is my answer
I would get a 2nd opinion on this, though