SOLUTION: An excursion boat travels up river to a landing than returns to its starting point. The trip upriver takes 2.3 hours, and the trip back takes 1.8 hours. If the average speed on the

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Question 1088662: An excursion boat travels up river to a landing than returns to its starting point. The trip upriver takes 2.3 hours, and the trip back takes 1.8 hours. If the average speed on the return trip is 5 mph faster than the trip up river, what is the boat’s speed up river? Hint: Distance = rate * time. Draw a table.ate * time. Draw a table.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +s+ = the speed going upriver in mi/hr
+s+%2B+5+ = the speed going downriver in mi/hr
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(1) +d+=+s%2A2.3+
and
(2) +d+=+%28+s+%2B+5+%29%2A1.8+
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(2) +d+=+1.8s+%2B+9+
Plug (1) into (2)
(2) +2.3s+=+1.8s+%2B+9+
(2) +.5s+=+9+
(2) +s+=+18+
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The speed upriver is 18 mi/hr
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To make a table, you have:
[ upriver speed, s ], [ downriver speed, s+5 ],
[ upriver time ], [ downriver time ]
[ upriver distance, d ] = [ downriver distance, d ]