document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1163882>Question 1163882</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Two years ago a man was 7 times older than his son but in three years he will be only four times as old as his son.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 #788119 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=788119\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> m = number of years old the man is  now.<BR>\n" );
document.write( "s = number of years old his sone is now.\r<BR>\n" );
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document.write( "two years ago, the man was 7 times older than his son.\r<BR>\n" );
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document.write( "there is a difference between 7 times as old and 7 times older.<BR>\n" );
document.write( "7 times as old says that a = 7 * b<BR>\n" );
document.write( "7 times older says that a = b + 7*b = 8*b\r<BR>\n" );
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document.write( "your problem statement seems to mix them both.<BR>\n" );
document.write( "i suspect you meant as old as, rather than older than.\r<BR>\n" );
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document.write( "i'll assume that, therefore, i'll rephrase the problem statement to say:\r<BR>\n" );
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document.write( "Two years ago a man was 7 times as old as his son, but in three years he will be only four times as old as his son.<BR>\n" );
document.write( "How old are they?\r<BR>\n" );
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document.write( "your formulas are:\r<BR>\n" );
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document.write( "(m - 2) = 7 * (s - 2)<BR>\n" );
document.write( "(m + 3) = 4 * (s + 3)\r<BR>\n" );
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document.write( "simplify these formulas to get:\r<BR>\n" );
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document.write( "m - 2 = 7 * s - 14<BR>\n" );
document.write( "m + 3 = 4 * s + 12\r<BR>\n" );
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document.write( "solve for m in both equations to get:\r<BR>\n" );
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document.write( "m =  7 * s - 12<BR>\n" );
document.write( "m = 4 * s + 9\r<BR>\n" );
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document.write( "subtract the second equation from the first to get  0 = 3 * s - 21<BR>\n" );
document.write( "add 21 to both sides of this equation to get 21 = 3 * s<BR>\n" );
document.write( "solve for s to get s = 7\r<BR>\n" );
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document.write( "2 years ago, the son was 5 and the man was 7 * 5 = 35<BR>\n" );
document.write( "that means the man is currently 37 years old and his son is 7.\r<BR>\n" );
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document.write( "3 years from now, the man will be 40 and his son will be 10.<BR>\n" );
document.write( "40 / 10 = 4 which means that the man will be 4 times as old as his son.\r<BR>\n" );
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document.write( "looks like man is 37 years old and his son is 7.\r<BR>\n" );
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document.write( "two years ago, 35/5 = 7<BR>\n" );
document.write( "3 years from now, 40/10 = 4<BR>\n" );
document.write( "solution looks good.<BR>\n" );
document.write( "solution is man is 37 years old and his son is 7.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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