document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1005619>Question 1005619</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the sum of the ages of a father and a son is 56. Four years ago the father was 3 times as old as the son. find the age of each  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #621794 by </B><A HREF=/tutors/aboutme.mpl?userid=addingup><B>addingup(3677)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=addingup><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=addingup><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=621794\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> f+s= 56 if we subtract s from both sides:<BR>\n" );
document.write( "f= 56-s We'll use this value for f in the next equation<BR>\n" );
document.write( "----------------<BR>\n" );
document.write( "f-4= 3s Substitute for f:<BR>\n" );
document.write( "(56-s)-4= 3s<BR>\n" );
document.write( "56-s-4= 3s add s on both sides and do subtraction on left:<BR>\n" );
document.write( "52= 4s Divide both sides by 4<BR>\n" );
document.write( "s= 13 The son is 13 and the father is:<BR>\n" );
document.write( "56-13= 43<BR>\n" );
document.write( "J </SPAN>\n" );
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