document.write( "Question 1126967: Alex is 15 years older than Cristina. In 4 years, the sum of their ages will be 91. How old are they now? \n" ); document.write( "

Algebra.Com's Answer #743297 by ikleyn(52794) $\"\"$ $\"About$

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document.write( "A = C + 15            (1)    (\"Alex is 15 years older than Cristina.\")\r\n" );
document.write( "(A+4) + (C+4) = 91    (2)    (\"In 4 years, the sum of their ages will be 91\")\r\n" );
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document.write( "Substitute expression A = C+15  from eq(1) into eq(2). You will get\r\n" );
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document.write( "((C+15)+4) + (C+4) = 91\r\n" );
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document.write( "2C + 15 + 4 + 4 = 91\r\n" );
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document.write( "2C = 91 - 15 - 4 - 4 = 68  ====>\r\n" );
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document.write( "C = 68/2 = 34.\r\n" );
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document.write( "Answer.  C is 34 years old.  A is 34+15 = 49 years old.  \r\n" );
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document.write( "Check.   (34+4) + (49+4) = 38 + 53 = 91.   ! Correct !\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
\n" ); document.write( "\n" ); document.write( "    - Age problems for mental solution \r
\n" ); document.write( "\n" ); document.write( "in this site.\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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\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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