document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=166972>Question 166972</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Anna made the following announcement:\r<BR>\n" );
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document.write( "\" In 7 years, I will be half my mother's age. Thirteen years ago, she was 6 times as old as I was then.\"<BR>\n" );
document.write( "How old is Anna now?\r<BR>\n" );
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document.write( "My teacher gives us a \"problem of the week\" every week and this is it. I'm not sure how to figure out the answer. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #122996 by </B><A HREF=/tutors/aboutme.mpl?userid=Alan3354><B>Alan3354(69443)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Alan3354><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=Alan3354><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=122996\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Anna made the following announcement: <BR>\n" );
document.write( "\" In 7 years, I will be half my mother's age. Thirteen years ago, she was 6 times as old as I was then.\"<BR>\n" );
document.write( "How old is Anna now? <BR>\n" );
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document.write( "A = Anna's age<BR>\n" );
document.write( "M = Mother's age<BR>\n" );
document.write( "In 7 years, I will be half my mother's age.<BR>\n" );
document.write( "M+7 = 2*(A+7)<BR>\n" );
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document.write( "Thirteen years ago, she was 6 times as old as I was then.<BR>\n" );
document.write( "M-13 = 6*(A-13)<BR>\n" );
document.write( "Now there are 2 eqns in 2 unknowns.<BR>\n" );
document.write( "M + 7 = 2A+14 eqn 1<BR>\n" );
document.write( "M -13 = 6A-78 eqn 2<BR>\n" );
document.write( "3M+21 = 6A+42 eqn 1 times 3<BR>\n" );
document.write( "Subtract<BR>\n" );
document.write( "-2M-34= -120<BR>\n" );
document.write( "-2M = -86<BR>\n" );
document.write( "M = 43  (Mother's age)<BR>\n" );
document.write( "Sub into eqn 1<BR>\n" );
document.write( "43+7 = 2A + 14<BR>\n" );
document.write( "2A = 36<BR>\n" );
document.write( "A = 18  (Anna's age)<BR>\n" );
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document.write( "Check:<BR>\n" );
document.write( "13 years ago, they were ages 5 and 30, = 6 times.<BR>\n" );
document.write( "In 7 years, they'll be 25 and 50, 2 times.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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