document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=972136>Question 972136</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Please help me solve this word problem.<BR>\n" );
document.write( "A rowing crew practices at a steady rate of 9 miles per hour. When they practice in steadily flowing river, a 10-mile trip downstream takes the same time as a 5-mile trip upstream. What is the rate of the river current?\r<BR>\n" );
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document.write( "I have tried 9/10 = 0.9<BR>\n" );
document.write( "I have tried dividing 9/5 = 1.8<BR>\n" );
document.write( "I have tried (10+5)/9 = 1.7<BR>\n" );
document.write( "I have tried (9*10)/5 = 18<BR>\n" );
document.write( "I have tried 9=10/x ~ 9/10 =.9 ~ .9*5  = 4.5\r<BR>\n" );
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document.write( "I do not know how to figure out the answer. It would be helpful if i could have a formula for solving the problem. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #594502 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=594502\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> speed= rowing speed + current or - current<BR>\n" );
document.write( "r=rowing speed, c=current<BR>\n" );
document.write( "distance = speed * time\r<BR>\n" );
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document.write( "10=9t +ct, where t=time  t= 10/(9+c)<BR>\n" );
document.write( "5=9t-ct, because it is the same time   t=5/(9-c)\r<BR>\n" );
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document.write( "[10/(9+c)]=[5/(9-c)]\r<BR>\n" );
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document.write( "cross-multiply\r<BR>\n" );
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document.write( "90-10c=45 +5c<BR>\n" );
document.write( "45=15c<BR>\n" );
document.write( "3=c\r<BR>\n" );
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document.write( "speed downstream is 12 mph, and it takes (10/12) hours to cover 10 miles<BR>\n" );
document.write( "speed upstream is 6 mph, and it takes (5/6) hours to cover 5 miles. Those fractions are equivalent. </SPAN>\n" );
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