document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1009724>Question 1009724</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A boy is 12 years old . his father is four times as old. In x years' time, the father will be three times as old as the son. Calculate the value of x. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #625178 by </B><A HREF=/tutors/aboutme.mpl?userid=ikleyn><B>ikleyn(52803)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ikleyn><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=ikleyn><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=625178\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> .<BR>\n" );
document.write( "A boy is 12 years old. His father is four times as old. In x years' time, the father will be three times as old as the son. Calculate the value of x.<BR>\n" );
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document.write( "According to the first part of the condition, the father is 48 years now.\r<BR>\n" );
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document.write( "The second part of the condition gives an equation\r<BR>\n" );
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document.write( "3*(x + 12) = x + 48.\r<BR>\n" );
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document.write( "Simplify and solve it:\r<BR>\n" );
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document.write( "3x + 36 = x + 48,\r<BR>\n" );
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document.write( "2x = 48 - 36 = 12,\r<BR>\n" );
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document.write( "x = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=12%2F2 ALIGN=MIDDLE  ALT=\"12%2F2\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 6.\r<BR>\n" );
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document.write( "<U>Answer</U>. In 6 years.\r<BR>\n" );
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