document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=754345>Question 754345</A>: <I><SPAN STYLE=\"word-break: break-all;\"> the age of the father is twice the sum of the ages of his two children. after 20 years, his age will be equal to the sum of the ages of his children. find the age of the father </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #458992 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=458992\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> let x = the age of the father today.<BR>\n" );
document.write( "let w = the sum of the ages of the children today.\r<BR>\n" );
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document.write( "since the age of the father today is 2 times the sum of the age of the children today, the formula for that will be:\r<BR>\n" );
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document.write( "x = 2w\r<BR>\n" );
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document.write( "in 20 years, the age of the father will be x + 20.<BR>\n" );
document.write( "in 20 years, the sum of the age of the children will be w + 40.<BR>\n" );
document.write( "this is because each child has aged 20 years, so the sum of the years the 2 children have aged is 40.\r<BR>\n" );
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document.write( "the formula for the age of the father the the sum of the ages of the children in 20 years becomes:\r<BR>\n" );
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document.write( "x + 20 = w + 40\r<BR>\n" );
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document.write( "you have 2 equations that need to be solved simultaneously.\r<BR>\n" );
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document.write( "they are:\r<BR>\n" );
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document.write( "x = 2w<BR>\n" );
document.write( "x + 20 = w + 40\r<BR>\n" );
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document.write( "because x = 2w from the first equation, replace x with 2w in the second equation to get:\r<BR>\n" );
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document.write( "2w + 20 = w + 40\r<BR>\n" );
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document.write( "solve for w to get:\r<BR>\n" );
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document.write( "w = 20\r<BR>\n" );
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document.write( "since x = 2w, this means that x = 40\r<BR>\n" );
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document.write( "the age of the father today is 40.<BR>\n" );
document.write( "the sum of the age of the children today is 20<BR>\n" );
document.write( "the age of the father today is 2 times the sum of the age of the children today.\r<BR>\n" );
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document.write( "the age of the father 20 years from now is 60.<BR>\n" );
document.write( "the sum of the age of the children 20 years from now is 20 + 40 = 60.<BR>\n" );
document.write( "the age of the father 20 years from now is equal to the sum of the age of the children 20 years from now.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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