document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1145713>Question 1145713</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The sum of Sam and Mary's age is 60. Twelve years ago, Sam was three times as old as Mary.\r<BR>\n" );
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document.write( "1. Write a system of equations to represent this situation.\r<BR>\n" );
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document.write( "2. Find Mary's age now </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #766968 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=766968\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The sum of Sam and Mary's age is 60.<BR>\n" );
document.write( "s + m = 60<BR>\n" );
document.write( "m = (60-s)<BR>\n" );
document.write( " Twelve years ago, Sam was three times as old as Mary.<BR>\n" );
document.write( "s - 12 = 3(m-12)<BR>\n" );
document.write( "s - 12 = 3m - 36<BR>\n" );
document.write( "s = 3m - 36 + 12<BR>\n" );
document.write( "s = 3m - 24<BR>\n" );
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document.write( "1. Write a system of equations to represent this situation.<BR>\n" );
document.write( "in the above equation, replace m with 60-s<BR>\n" );
document.write( "s = 3(60-s) - 24<BR>\n" );
document.write( "s = 180 - 3s - 24<BR>\n" );
document.write( "s + 3s = 180 - 24<BR>\n" );
document.write( "4s = 156<BR>\n" );
document.write( "s = 156/4<BR>\n" );
document.write( "s = 39 yrs is sam's age<BR>\n" );
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document.write( "2. Find Mary's age now<BR>\n" );
document.write( "60 - 39 = 21 yrs is Mary's age<BR>\n" );
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document.write( "See if that checks out<BR>\n" );
document.write( "39 - 12 = 3(21-12)<BR>\n" );
document.write( "27 = 3(9) </SPAN>\n" );
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