document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=323929>Question 323929</A>: <I><SPAN STYLE=\"word-break: break-all;\">   Robert is 4/5 as old as Joel. Four years ago, he was 3/4 as old as Joel, how old are they now? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #231818 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20056)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><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=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=231818\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "Robert<font color = \"red\">, who is now R years old,</font> is 4/5 as old as Joel<font color = \"red\">, who is now J years old</font>. <BR>\n" );
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document.write( "So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=R ALIGN=MIDDLE  ALT=\"R\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4%2F5 ALIGN=MIDDLE  ALT=\"4%2F5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=J ALIGN=MIDDLE  ALT=\"J\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Four years ago <font color = \"red\">when Robert was R-4</font>, he was 3/4 as old as Joel <font color = \"red\">was four years ago, which was J-4</font>.<BR>\n" );
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document.write( "So <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=R-4 ALIGN=MIDDLE  ALT=\"R-4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%22%22=%22%22 ALIGN=MIDDLE  ALT=\"%22%22=%22%22\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=3%2F4 ALIGN=MIDDLE  ALT=\"3%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28J-4%29 ALIGN=MIDDLE  ALT=\"%28J-4%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Therefore we have the system of equations:<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28R=%284%2F5%29J%2C+R-4=%283%2F4%29%28J-4%29%29 ALIGN=MIDDLE  ALT=\"system%28R=%284%2F5%29J%2C+R-4=%283%2F4%29%28J-4%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Clear them of fractions:<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%285R=4J%2C+4%28R-4%29=3%28J-4%29%29 ALIGN=MIDDLE  ALT=\"system%285R=4J%2C+4%28R-4%29=3%28J-4%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Can you solve that system?  If not post again asking how.<BR>\n" );
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document.write( "R=16, J=20<BR>\n" );
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document.write( "  Robert<font color = \"red\">, who is 16,</font> is 4/5 as old as Joel <font color = \"red\">, who is 20, and indeed 4/5 of 20 = (4/5)x(20)=16</font>. Four years ago, <font color = \"red\">he was 16 and Joel was 12, that is,</font> 3/4 as old as Joel<font color = \"red\">, and indeed 3/4 of 16 is (3/4)x(16)=12</font>. \r<BR>\n" );
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document.write( "Edwin</pre> </SPAN>\n" );
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