document.write( "Question 1151350: In 3 years, Susan will be three times as old as his daughter. Three years ago, the sum of their ages was 56. What is the daughter's age now? \n" ); document.write( "

Algebra.Com's Answer #773096 by ikleyn(52803) $\"\"$ $\"About$

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\n" ); document.write( "In 3 years, Susan will be three times as old as $\"highlight%28cross%28his%29%29\"$ her daughter. Three years ago, the sum of their ages was 56.
\n" ); document.write( "What is the daughter's age now?
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document.write( "m, Susan the mother\r\n" );
document.write( "d, daughter\r\n" );
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document.write( "From the description, you have this system of 2 equations\r\n" );
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document.write( "    m + 3 = 3*(d+3),      (1)\r\n" );
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document.write( "    (m-3) + (d-3) = 56.   (2)\r\n" );
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document.write( "From equation (1), express  m = 3d + 6  and substitute it into equation (2). You will get\r\n" );
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document.write( "    ((3d+6) - 3) + (d-3) = 56,\r\n" );
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document.write( "    4d                   = 56\r\n" );
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document.write( "      d                  = 56/4 = 14.\r\n" );
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document.write( "ANSWER.  The daughter is 14 years old now.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "The solution and the answer by @josgarithmetic, giving 28 years for the daughter, is W R O N G.\r
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\n" ); document.write( "\n" ); document.write( "For your safety, ignore it (!)\r
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