document.write( "Question 894437: A motorboat travels 220km in 4 hours going upstream. It travels
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Algebra.Com's Answer #542058 by MathTherapy(10552) $\"\"$ $\"About$

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\n" ); document.write( "A motorboat travels 220km in 4 hours going upstream. It travels
\n" ); document.write( "284km going downstream in the same amount of time. What is the rate of the boat in still water and what is the rate of the current?
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document.write( "Speed at which it travels, going upstream = , or 55 km/h
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document.write( "Speed at which it travels, going downstream = , or 71 km/h
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document.write( "Let rate of boat in still water be S, and the current, C
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document.write( "Traveling upstream, it'd be going AGAINST the current, so we can say that: S - C = 55 ------ eq (i)
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document.write( "Traveling downstream, it'd be going WITH the current, so we can say that:  S + C = 71 ------ eq (ii)
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document.write( "2S = 126 ------ Adding eqs (i) & (ii)
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document.write( "S, or speed of boat in still water = , or  km/h\r
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document.write( "63 - C = 55 ------- Substituting 63 for S in eq (i)
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document.write( "- C = 55 - 63
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document.write( "- C = - 8
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document.write( "C, or speed of current = , or  km/h \n" );
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