document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=281515>Question 281515</A>: <I><SPAN STYLE=\"word-break: break-all;\"> a man is 5times as old as his son. In 5 years he will be only 3 times as old as his son, find the present age? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #204510 by </B><A HREF=/tutors/aboutme.mpl?userid=Mathematicians><B>Mathematicians(84)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Mathematicians><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=Mathematicians><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=204510\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> These word problems are always tricky, basically you want to set up two equations in order to find both their ages.\r<BR>\n" );
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document.write( "From the first sentence, \"a man is  5 times as old as his son\"\r<BR>\n" );
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document.write( "I will let X be the age of the old guy and Y be the age of his son:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+=+5Y ALIGN=MIDDLE  ALT=\"X+=+5Y\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "You can test that this equation is right, if his son was 1 years old, then the man would be 5 which is 5 times more then 1!\r<BR>\n" );
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document.write( "Continuing on with the second sentence\r<BR>\n" );
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document.write( "In 5 years he will be only 3 times as old as his son, find the present age?\r<BR>\n" );
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document.write( "If 5 years progress, both him and his son will have to add 5 years so:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+%2B+5+=+3%28Y+%2B+5%29 ALIGN=MIDDLE  ALT=\"X+%2B+5+=+3%28Y+%2B+5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "To solve this equation, we know that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+=+5Y ALIGN=MIDDLE  ALT=\"X+=+5Y\"   DISABLED_style= \"max-width:90%; height:auto;\" > so we plug in 5Y for every X.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+%2B+5+=+3%28Y+%2B+5%29 ALIGN=MIDDLE  ALT=\"X+%2B+5+=+3%28Y+%2B+5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > becomes<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5Y+%2B+5+=+3%28Y+%2B+5%29 ALIGN=MIDDLE  ALT=\"5Y+%2B+5+=+3%28Y+%2B+5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > Using distribution <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=5Y+%2B+5+=+3Y+%2B+15 ALIGN=MIDDLE  ALT=\"5Y+%2B+5+=+3Y+%2B+15\"   DISABLED_style= \"max-width:90%; height:auto;\" > Subtract 3Y on both sides and 5 on both sides<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2Y++=+10 ALIGN=MIDDLE  ALT=\"2Y++=+10\"   DISABLED_style= \"max-width:90%; height:auto;\" > Finally divide both sides by 2<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=Y+=+5 ALIGN=MIDDLE  ALT=\"Y+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Which says his son is 5 years old, how old is the man?\r<BR>\n" );
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document.write( "Go back to any equation, this will be easiest with this one:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+=+5Y ALIGN=MIDDLE  ALT=\"X+=+5Y\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+=+5%2A5 ALIGN=MIDDLE  ALT=\"X+=+5%2A5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=X+=+25 ALIGN=MIDDLE  ALT=\"X+=+25\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "The man is 25 and his son is 5.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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