document.write( "Question 329308: Junior’s boat will go 15 miles per
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\n" ); document.write( "same amount of time as it takes to go 9 miles upstream,
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Algebra.Com's Answer #236155 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
Rate*Time=Distance
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\n" ); document.write( "Let W be the speed of the current,
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\n" ); document.write( "1.\"%2815%2BW%29%2At=12\"<-- with the current
\n" ); document.write( "2.\"%2815-W%29%2At=9\"<--- against the current
\n" ); document.write( "From eq. 1,
\n" ); document.write( "\"15%2BW=12%2Ft\"
\n" ); document.write( "From eq. 2,
\n" ); document.write( "\"15-W=9%2Ft\"
\n" ); document.write( "Add those two results,
\n" ); document.write( "\"15%2BW%2B15-W=21%2Ft\"
\n" ); document.write( "\"30=21%2Ft\"
\n" ); document.write( "\"t=21%2F30\"
\n" ); document.write( "Then from eq. 1,
\n" ); document.write( "\"15%2BW=12%2830%2F21%29=120%2F7\"
\n" ); document.write( "\"W=120%2F7-105%2F7\"
\n" ); document.write( "\"W=15%2F7\"mph
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