document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=165896>Question 165896</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Fred is 3 yrs. older than his sister Mary. In 7 yrs she will be 6/7 of his age. How old are they?  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #122279 by </B><A HREF=/tutors/aboutme.mpl?userid=midwood_trail><B>midwood_trail(310)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=midwood_trail><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/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=122279\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Fred is 3 years older than his sister Mary. In 7 yrs she will be 6/7 of his age. How old are they?\r<BR>\n" );
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document.write( "Mary's age now = x\r<BR>\n" );
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document.write( "Fred's age now = x + 3\r<BR>\n" );
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document.write( "In seven years each person will be 7 years older, right?\r<BR>\n" );
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document.write( "Here's how we represent that:\r<BR>\n" );
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document.write( "Mary = x + 7\r<BR>\n" );
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document.write( "Fred = (x + 3) + 7\r<BR>\n" );
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document.write( "We now multiply (6/7) times Fred's age 7 years form now.\r<BR>\n" );
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document.write( "The equation looks like this: \r<BR>\n" );
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document.write( "x + 7 = (6/7)(x + 3) + 7\r<BR>\n" );
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document.write( "We multiply every term by 7 (our LCD).\r<BR>\n" );
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document.write( "Doing so, we get this:\r<BR>\n" );
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document.write( "7x + 49 = 6x + 18 + 49\r<BR>\n" );
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document.write( "We now combine like terms:\r<BR>\n" );
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document.write( "7x - 6x = -49 + 67\r<BR>\n" );
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document.write( "x = 18\r<BR>\n" );
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document.write( "Mary is 18 years old.\r<BR>\n" );
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document.write( "Fred is 18 + 3 = 21 years old.\r<BR>\n" );
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document.write( "Did you follow? </SPAN>\n" );
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