document.write( "Question 1059114: A boat moves 7 kilometers upstream
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\n" ); document.write( "rate of the boat in still water. \n" ); document.write( "

Algebra.Com's Answer #674219 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "A boat moves 7 kilometers upstream in the same amount of time it moves 20 kilometers downstream. If the rate of the current is 5 kilometers per hour, find the rate of the boat in still water.
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Let boat's rate be S
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document.write( "Average speed:  
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document.write( "Time boat takes to travel 7 miles upstream = 
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document.write( "Time boat takes to travel 20 miles downstream = 
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document.write( "We then get the following TIME equation: 
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document.write( "20(S - 5) = 7(S + 5) ------ Cross-multiplying
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document.write( "20S - 100 = 7S + 35
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document.write( "20S - 7S = 35 + 100
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document.write( "13S = 135
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document.write( "S, or speed of boat in still water =  \n" );
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