document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=661570>Question 661570</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Kurt is 12 years younger than Mark. When Mark's age is increased by 20% and Kurt's age is increased by 25%, the sum of their ages is 83. Find Kurt's age.\r<BR>\n" );
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document.write( "I am having a hard time coming up with the equation to solve.  I think the answer is 28, but I need an algebraic equation to solve.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #411683 by </B><A HREF=/tutors/aboutme.mpl?userid=kevwill><B>kevwill(135)</B></A><img src=\"/images/stars/stars-09.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=kevwill><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=kevwill><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=411683\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let k = Kurt's age and m = Mark's age.  From the first sentence we have<BR>\n" );
document.write( "k = m - 12<BR>\n" );
document.write( "From the second sentence we have:<BR>\n" );
document.write( "m*1.2 + k*1.25 = 83<BR>\n" );
document.write( "Substituting the first equation into the second gives:<BR>\n" );
document.write( "m*1.2 + (m-12)*1.25 = 83<BR>\n" );
document.write( "Expanding:<BR>\n" );
document.write( "m*1.2 + m*1.25 - 15 = 83<BR>\n" );
document.write( "m*2.45 - 15 = 83<BR>\n" );
document.write( "m*2.45 = 98<BR>\n" );
document.write( "m = 98 / 2.45 = 40<BR>\n" );
document.write( "So Mark is 40 and Kurt is 28.<BR>\n" );
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