document.write( "Question 974580: Meg rowed her boat upstream a distance of 20 miles and then rowed back to the starting point. The total time of the trip was 12 hours. If the rate of the current was 4 mph, find the average speed of the boat relative to the water \n" ); document.write( "

Algebra.Com's Answer #596461 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "Meg rowed her boat upstream a distance of 20 miles and then rowed back to the starting point. The total time of the trip was 12 hours. If the rate of the current was 4 mph, find the average speed of the boat relative to the water
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Let average speed in still water be S
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document.write( "Time taken to travel upstream:  
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document.write( "Time taken to travel downstream: 
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document.write( "We then get: 
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document.write( "20(S + 4) + 20(S – 4) = 12(S – 4)(S + 4) ---- Multiplying by LCD, (S – 4)(S + 4)
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document.write( "(S – 6)(3S + 8) = 0
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document.write( "S, or speed of boat in still water =  mph \n" );
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