document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1165625>Question 1165625</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of the ages of mark and Sarah is 102 years. 11 years ago mark was 3 times Sarah’s age. How old is mark now?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #790248 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=790248\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> m represents mark's age and s represents sarah's age.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the sum of their ages is 102, therefore:<BR>\n" );
document.write( "m + s = 102\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "11 years ago, mark was 3 times sarah's age, therefore:<BR>\n" );
document.write( "m - 11 = 3 * (s - 11)\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "solve for m in the first equation to get:<BR>\n" );
document.write( "m = 102 - s.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "replace m with 102 - s in the second equation to get:<BR>\n" );
document.write( "m - 11 = 3 * (s - 11) becomes:<BR>\n" );
document.write( "102 - s - 11 = 3 * (s - 11).<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "102 - s - 11 = 3 * s - 33.<BR>\n" );
document.write( "add s to both sides of the equation andeadd 33 to both sides of the equation to get:<BR>\n" );
document.write( "102  - 11 + 33 = 4 * s<BR>\n" );
document.write( "simplify to get:<BR>\n" );
document.write( "124 = 4 * s.<BR>\n" );
document.write( "solve for s to get:<BR>\n" );
document.write( "s = 124 / 4 = 31.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "since m + s = 124 and s = 31, then m = 124 - 31 = 71<BR>\n" );
document.write( "you have:<BR>\n" );
document.write( "m = 71<BR>\n" );
document.write( "s = 34\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "m + s = 102<BR>\n" );
document.write( "m - 11 = 3 * (s - 11) becomes:<BR>\n" );
document.write( "71 - 11 = 3 * (31 - 12) which becomes;<BR>\n" );
document.write( "60 = 3 * 20 which is true.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "the requirements of the problem are satisfied.<BR>\n" );
document.write( "the solution is that mark is 71 years old now.<BR>\n" );
document.write( "additional information is that sarah is 31 years old now.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );