document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=315459>Question 315459</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Ten years ago a father was seven times as old as his son, two years hence twice his age will be equal to five times his sons. what is the present age of son? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #225747 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=225747\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ten years ago a father was seven times as old as his son,<BR>\n" );
document.write( " two years hence twice his age will be equal to five times his sons.<BR>\n" );
document.write( " what is the present age of son?<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Write an equation for each statement, simplify:<BR>\n" );
document.write( "\"Ten years ago a father was seven times as old as his son,\"<BR>\n" );
document.write( "f - 10 = 7(s-10)<BR>\n" );
document.write( "f - 10 = 7s - 70<BR>\n" );
document.write( "f = 7s - 70 + 10<BR>\n" );
document.write( "f = 7s - 60<BR>\n" );
document.write( ":<BR>\n" );
document.write( "\"two years hence twice his age will be equal to five times his sons.\"<BR>\n" );
document.write( "2(f + 2) = 5(s+2)<BR>\n" );
document.write( "2f + 4 = 5s + 10<BR>\n" );
document.write( "2f = 5s + 10 - 4<BR>\n" );
document.write( "2f = 5s + 6<BR>\n" );
document.write( ":<BR>\n" );
document.write( "what is the present age of son?<BR>\n" );
document.write( "Replace f with (7s-60) in the above equation:<BR>\n" );
document.write( "2(7s - 60) = 5s + 6<BR>\n" );
document.write( "14s - 120 = 5s + 6<BR>\n" );
document.write( "14s = 5s + 6 + 120<BR>\n" );
document.write( "14s - 5s = 126<BR>\n" );
document.write( "9s = 126<BR>\n" );
document.write( "s = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=126%2F9 ALIGN=MIDDLE  ALT=\"126%2F9\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "s = 14 yrs, son's present age<BR>\n" );
document.write( ":<BR>\n" );
document.write( ":<BR>\n" );
document.write( "Check solution, find father's age<BR>\n" );
document.write( "f = 7s - 60<BR>\n" );
document.write( "f = 7(14) - 60<BR>\n" );
document.write( "f = 98 - 60<BR>\n" );
document.write( "f = 38 yrs, father's age<BR>\n" );
document.write( ":<BR>\n" );
document.write( "\"Ten years ago a father was seven times as old as his son, \"<BR>\n" );
document.write( "38 - 10 = 7(14-10)<BR>\n" );
document.write( "28 = 7(4)<BR>\n" );
document.write( "and<BR>\n" );
document.write( "\"two years hence twice his age will be equal to five times his sons.\"<BR>\n" );
document.write( "2(38+2) = 5(14 + 2)<BR>\n" );
document.write( "80 = 5(16); confirms our solution<BR>\n" );
document.write( ":<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );