document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=313306>Question 313306</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A man is three times as old as his son, and his daughter is four years younger than his son. If the combined ages of all three is 81 years, find the present age of the father. \r<BR>\n" );
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document.write( "Ps: Thank you, please demonstrate the work progress so I will know how to do the question next time please and thank you :D </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #224040 by </B><A HREF=/tutors/aboutme.mpl?userid=ntnk><B>ntnk(54)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ntnk><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=224040\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> So for these you have to turn the statements in the word problem into equations. \r<BR>\n" );
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document.write( "A man is three times as old as his son: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+M+=+3+%2A+S+ ALIGN=MIDDLE  ALT=\"+M+=+3+%2A+S+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "his daughter is four years younger than his son: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+D+=+S+-+4+ ALIGN=MIDDLE  ALT=\"+D+=+S+-+4+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "combined ages of all three is 81 years: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+M+%2B+D+%2B+S+=+81+ ALIGN=MIDDLE  ALT=\"+M+%2B+D+%2B+S+=+81+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "Now you can just substitute: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+%283%2AS%29+%2B+%28S-4%29+%2BS+=+81+ ALIGN=MIDDLE  ALT=\"+%283%2AS%29+%2B+%28S-4%29+%2BS+=+81+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+5%2AS+-+4+=+81+ ALIGN=MIDDLE  ALT=\"+5%2AS+-+4+=+81+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "Add 4 to both sides to get: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5%2AS+=+85+ ALIGN=MIDDLE  ALT=\"5%2AS+=+85+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "Divide by 5 on both sides to get: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+S+=+17+ ALIGN=MIDDLE  ALT=\"+S+=+17+\"   DISABLED_style= \"max-width:90%; height:auto;\" > \r<BR>\n" );
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document.write( "Now check: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+M+=+3+%2A+S+=+3+%2A+17+=+51+ ALIGN=MIDDLE  ALT=\"+M+=+3+%2A+S+=+3+%2A+17+=+51+\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+D+=+S+-+4+=+17+-+4+=+13+ ALIGN=MIDDLE  ALT=\"+D+=+S+-+4+=+17+-+4+=+13+\"   DISABLED_style= \"max-width:90%; height:auto;\" >, <BR>\n" );
document.write( "so <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+M+%2B+D+%2B+S+=+51+%2B+13+%2B+17+=+81+ ALIGN=MIDDLE  ALT=\"+M+%2B+D+%2B+S+=+51+%2B+13+%2B+17+=+81+\"   DISABLED_style= \"max-width:90%; height:auto;\" >, so we do indeed get the combined age as 81, which means our son's age of 17 is correct! \r<BR>\n" );
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document.write( "I hope that helps! \r<BR>\n" );
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document.write( "-ntnk  </SPAN>\n" );
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