document.write( "Question 1107789: Jane took 30 min to drive her boat upstream to​ water-ski at her favorite spot. Coming back later in the​ day, at the same boat​ speed, took her 15 min. If the current in that part of the river is 6 km per​ hr, what was her boat speed in still​ water? \n" ); document.write( "
Algebra.Com's Answer #853851 by timofer(144)\"\" \"About 
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Same distance each way.
\n" ); document.write( "If b is for the boat speed when no current, then
\n" ); document.write( "upstream distance \"%28b-6%29%281%2F2%29\"
\n" ); document.write( "downstream, same distance \"%28b%2B6%29%281%2F4%29\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%28b-6%29%2F2=%28b%2B6%29%2F4\"\r
\n" ); document.write( "\n" ); document.write( "\"2%28b-6%29=b%2B6\"\r
\n" ); document.write( "\n" ); document.write( "\"2b-12=b%2B6\"\r
\n" ); document.write( "\n" ); document.write( "\"b=6%2B12\"\r
\n" ); document.write( "\n" ); document.write( "\"b=18\"-----------------------------speed of boat without a current
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