document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=223211>Question 223211</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Sigh!  I just don't get this stuff : (  Very frustrating. Please help.\r<BR>\n" );
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document.write( "A boat can maintain a speed of 16mph. The boat makes a trip upstream in 20 mins. The return trip takes 15 minutes.  What is the speed of the current? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #166981 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=166981\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A boat can maintain a speed of 16mph. <BR>\n" );
document.write( "The boat makes a trip upstream in 20 mins.<BR>\n" );
document.write( " The return trip takes 15 minutes. What is the speed of the current?<BR>\n" );
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document.write( "Change min to hrs:<BR>\n" );
document.write( "15 min = 15/60 = 1/4 hr<BR>\n" );
document.write( "20 min = 20/60 = 1/3 hr<BR>\n" );
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document.write( "Let c = speed of the current<BR>\n" );
document.write( "then we can say:<BR>\n" );
document.write( "(16 - c) = boat speed up stream<BR>\n" );
document.write( "and<BR>\n" );
document.write( "(16 + c) = boat speed down stream<BR>\n" );
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document.write( "The distance up and the distance back are equal. Write a distance equation<BR>\n" );
document.write( "Dist = time * speed<BR>\n" );
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document.write( "Up dist = down dist<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F3 ALIGN=MIDDLE  ALT=\"1%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >(16-c) = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=1%2F4 ALIGN=MIDDLE  ALT=\"1%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" >(16+c)<BR>\n" );
document.write( "Multiply both sides by 12 to get rid of those denominators<BR>\n" );
document.write( "4(16-c) = 3(16+c)<BR>\n" );
document.write( "64 - 4c = 48 + 3c<BR>\n" );
document.write( "64 - 48 = 3c + 4c <BR>\n" );
document.write( "16 = 7c<BR>\n" );
document.write( "c = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=16%2F7 ALIGN=MIDDLE  ALT=\"16%2F7\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "c = 2.2587 mph speed of the current<BR>\n" );
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document.write( "We can confirm this solution by finding the distance of each, should be equal<BR>\n" );
document.write( ".25(16 + 2.2587) = 4.57 miles<BR>\n" );
document.write( ".33(16 - 2.2587) = 4.57 miles </SPAN>\n" );
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