document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=769712>Question 769712</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A motorboat can maintain a constant speed of 16 miles per hour in still water. The boat makes a certain trip upstream in 20 minutes; the return trip takes 15 minutes. What is the speed of the current?<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #469000 by </B><A HREF=/tutors/aboutme.mpl?userid=josmiceli><B>josmiceli(19441)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josmiceli><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=josmiceli><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=469000\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+c+ ALIGN=MIDDLE  ALT=\"+c+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the speed of the current<BR>\n" );
document.write( "Let <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+ ALIGN=MIDDLE  ALT=\"+d+\"   DISABLED_style= \"max-width:90%; height:auto;\" > = the one-way distance of the trip<BR>\n" );
document.write( "You must convert the minutes to hours<BR>\n" );
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document.write( "Going upstream:<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+%28+16+-+c+%29%2A%28+20%2F60+%29+ ALIGN=MIDDLE  ALT=\"+d+=+%28+16+-+c+%29%2A%28+20%2F60+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Going downstream:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+%28+16+%2B+c+%29%2A%28+15%2F60+%29+ ALIGN=MIDDLE  ALT=\"+d+=+%28+16+%2B+c+%29%2A%28+15%2F60+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "---------------------------<BR>\n" );
document.write( "Substitute (1) into (2)<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+16+-+c+%29%2A%28+20%2F60+%29+=+%28+16+%2B+c+%29%2A%28+15%2F60+%29+ ALIGN=MIDDLE  ALT=\"+%28+16+-+c+%29%2A%28+20%2F60+%29+=+%28+16+%2B+c+%29%2A%28+15%2F60+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%28+16+-+c+%29%2A%28+1%2F3+%29+=+%28+16+%2B+c+%29%2A%28+1%2F4+%29+ ALIGN=MIDDLE  ALT=\"+%28+16+-+c+%29%2A%28+1%2F3+%29+=+%28+16+%2B+c+%29%2A%28+1%2F4+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Multiply both sides by <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+12+ ALIGN=MIDDLE  ALT=\"+12+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+4%2A%28+16+-+c+%29+=+3%2A%28+16+%2B+c+%29+ ALIGN=MIDDLE  ALT=\"+4%2A%28+16+-+c+%29+=+3%2A%28+16+%2B+c+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+64+-+4c+=+48+%2B+3c+ ALIGN=MIDDLE  ALT=\"+64+-+4c+=+48+%2B+3c+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+7c+=+16+ ALIGN=MIDDLE  ALT=\"+7c+=+16+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+c+=+16%2F7+ ALIGN=MIDDLE  ALT=\"+c+=+16%2F7+\"   DISABLED_style= \"max-width:90%; height:auto;\" > mi/hr<BR>\n" );
document.write( "---------------<BR>\n" );
document.write( "check:<BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+%28+16+%2B+16%2F7+%29%2A%28+15%2F60+%29+ ALIGN=MIDDLE  ALT=\"+d+=+%28+16+%2B+16%2F7+%29%2A%28+15%2F60+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+16%2A%28+1+%2B+1%2F7+%29%2A%28+1%2F4+%29+ ALIGN=MIDDLE  ALT=\"+d+=+16%2A%28+1+%2B+1%2F7+%29%2A%28+1%2F4+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+4%2A%28+8%2F7+%29+ ALIGN=MIDDLE  ALT=\"+d+=+4%2A%28+8%2F7+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(2) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+32%2F7+ ALIGN=MIDDLE  ALT=\"+d+=+32%2F7+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "and<BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+%28+16+-+16%2F7+%29%2A%28+20%2F60+%29+ ALIGN=MIDDLE  ALT=\"+d+=+%28+16+-+16%2F7+%29%2A%28+20%2F60+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+16%2A%28+1+-+1%2F7+%29%2A%28+1%2F3+%29+ ALIGN=MIDDLE  ALT=\"+d+=+16%2A%28+1+-+1%2F7+%29%2A%28+1%2F3+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+16%2A%28+6%2F7+%29%2A%281%2F3+%29+ ALIGN=MIDDLE  ALT=\"+d+=+16%2A%28+6%2F7+%29%2A%281%2F3+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+16%2A%28+2%2F7+%29+ ALIGN=MIDDLE  ALT=\"+d+=+16%2A%28+2%2F7+%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "(1) <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+d+=+32%2F7+ ALIGN=MIDDLE  ALT=\"+d+=+32%2F7+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "OK\r<BR>\n" );
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