document.write( "Question 1056553: Mary is three times as old as susan. Two years ago, the sum of their ages was twenty. How old are they now
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Algebra.Com's Answer #671669 by ikleyn(52786) $\"\"$ $\"About$

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\n" ); document.write( "Mary is three times as old as susan. Two years ago, the sum of their ages was twenty. How old are they now
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document.write( "The condition is this system of two equations\r\n" );
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document.write( "M = 3S,               (1)    (\"Mary is three times as old as susan.\")\r\n" );
document.write( "(M-2) + (S-2) = 20.   (2)    (\"Two years ago, the sum of their ages was twenty.\")\r\n" );
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document.write( "Substitute the expression 1) into equation (2). You will get\r\n" );
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document.write( "(3S -2) + (S-2) = 20,\r\n" );
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document.write( "4S - 4 = 20,\r\n" );
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document.write( "4S = 24,\r\n" );
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document.write( "S = .\r\n" );
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document.write( "S = 6.  Susan is 6 years old.\r\n" );
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document.write( "Then Mary is 3*6 = 18 years old.\r\n" );
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\n" ); document.write( "\n" ); document.write( "There is a bunch of lessons on age word problems \r
\n" ); document.write( "\n" ); document.write( "    - Age problems and their solutions\r
\n" ); document.write( "\n" ); document.write( "    - A fresh formulation of a traditional age problem\r
\n" ); document.write( "\n" ); document.write( "    - Really intricate age word problem\r
\n" ); document.write( "\n" ); document.write( "    - Selected age word problems from the archive\r
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\n" ); document.write( "\n" ); document.write( "Read them and become an expert in solving age problems.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this online textbook under the topic \"Age word problems\".\r
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