document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=286065>Question 286065</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A father is twice a old as his son is today. A few years back, he was thrice as old and half that number of years prior to that, he was 5 times as old; and 6 years before that, he was as old as his son is today. The father age is (in yrs)  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #207452 by </B><A HREF=/tutors/aboutme.mpl?userid=ptaylor><B>ptaylor(2198)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ptaylor><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=ptaylor><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=207452\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x=son's age today<BR>\n" );
document.write( "Then 2x=father's age today <BR>\n" );
document.write( "t years back, we have:<BR>\n" );
document.write( "x-t=son's age t years back <BR>\n" );
document.write( "2x-t=father's age t years back and we are told:<BR>\n" );
document.write( "2x-t=3(x-t)=<BR>\n" );
document.write( "2x-t=3x-3t<BR>\n" );
document.write( "x=2t-----------------------eq1<BR>\n" );
document.write( "t/2 years before this we have:<BR>\n" );
document.write( "x-t-t/2=x-3t/2=son's age half that number of years before that <BR>\n" );
document.write( "2x-3t/2=father's age half that number of years before that and we are told:<BR>\n" );
document.write( "2x-3t/2=5(x-3t/2)=<BR>\n" );
document.write( "2x-3t/2=5x-15t/2  multiply each term by 2<BR>\n" );
document.write( "4x-3t=10x-15t<BR>\n" );
document.write( "12t=6x<BR>\n" );
document.write( "or<BR>\n" );
document.write( "x=2t  or t=x/2 same as before----------------------eq2\r<BR>\n" );
document.write( "\n" );
document.write( "6 years before this<BR>\n" );
document.write( "x-(3t/2)-6=son's age<BR>\n" );
document.write( "2x-(3t/2)-6=fathers age and we are told that:<BR>\n" );
document.write( "2x-(3t/2)-6=x---------------eq3 multiply each term by 2<BR>\n" );
document.write( "4x-3t-12=2x<BR>\n" );
document.write( "2x-3t=12--------------eq3<BR>\n" );
document.write( "substitute t=x/2 in eq3<BR>\n" );
document.write( "2x-3(x/2)=12  multiply each term by 2<BR>\n" );
document.write( "4x-3x=24<BR>\n" );
document.write( "x=24---------son's age now<BR>\n" );
document.write( "t=x/2=12 years<BR>\n" );
document.write( "2x=2*24=48----father's age now<BR>\n" );
document.write( "CK<BR>\n" );
document.write( "12 years ago:<BR>\n" );
document.write( "son was 24-12=12<BR>\n" );
document.write( "father was 48-12=36 or 3*12<BR>\n" );
document.write( "6 years prior to that:<BR>\n" );
document.write( "son was 12-6=6<BR>\n" );
document.write( "father36-6=30 or 5*6<BR>\n" );
document.write( "6 years prior to that:<BR>\n" );
document.write( "father was 30-6=24 same as son's age now\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "Hope this helps--ptaylor </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );