document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=761851>Question 761851</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Tony'a outboard can drive her boat at 7mph in still water.  It takes her 10 minutes more to reach her friends camp 4 miles up the river than to return to her camp down river.  What is the speed of the current?\r<BR>\n" );
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document.write( "I have already asked this question on here before but got an incorrect answer. Be aware that it takes Tonya 10 minutes MORE not just 10 minutes. Here is my attempt<BR>\n" );
document.write( "going: 4=(7-c)*(t+10)          returning: 4=(7+c)*t<BR>\n" );
document.write( "$=(7-c)*((4/7+c)+10)<BR>\n" );
document.write( "Where do I go from here? You are so wonderful thank you so much!<BR>\n" );
document.write( "Forever in debt to strangers, Abby </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #463532 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=463532\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Tony'a outboard can drive her boat at 7mph in still water. It takes her 10 minutes more to reach her friends camp 4 miles up the river than to return to her camp down river. What is the speed of the current? <BR>\n" );
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document.write( "The speed is in mi/hr, so change 10 mins to 1/6 hour<BR>\n" );
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document.write( "c = current<BR>\n" );
document.write( "d = r*t<BR>\n" );
document.write( "4 = (7-c)*(t + 1/6) = (7+c)*t<BR>\n" );
document.write( "7t - ct -c/6 + 7/6 = 7t + ct<BR>\n" );
document.write( "That won't work<BR>\n" );
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document.write( "t = 4/(7+c)<BR>\n" );
document.write( "t + 1/6 = 4/(7-c)<BR>\n" );
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document.write( "Sub for t<BR>\n" );
document.write( "4/(7+c) + 1/6 = 4/(7-c)<BR>\n" );
document.write( "(24 + 7 + c)/(6(7+c)) = 4/(7-c)<BR>\n" );
document.write( "(31 + c)*(7-c) = 24(7+c)<BR>\n" );
document.write( "-c^2 + -24c + 217 = 24c + 168<BR>\n" );
document.write( "c^2 + 48c - 49 = 0<BR>\n" );
document.write( "(c-1)*(c+49) = 0<BR>\n" );
document.write( "c = 1 mi/hr<BR>\n" );
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