document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=766996>Question 766996</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A father is four times older than his son. However,20 years later, he will only be twice as old as the son.What is the father's 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 #467587 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=467587\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A father is four times older than his son. However,20 years later, he will only be twice as old as the son.What is the father's present age?<BR>\n" );
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document.write( "Now:<BR>\n" );
document.write( "F = 5S<BR>\n" );
document.write( "In 20 years:<BR>\n" );
document.write( "F+20 = 2(S+20)<BR>\n" );
document.write( "sub for F<BR>\n" );
document.write( "5S + 20 = 2S + 40<BR>\n" );
document.write( "3S = 20<BR>\n" );
document.write( "S = 20/3<BR>\n" );
document.write( "F = 100/3 years<BR>\n" );
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document.write( "PS  \"4 times older\" is not the same as \"4 times as old\" </SPAN>\n" );
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