document.write( "Question 1110523: A fine arts center charges $20 per adult and $10 per senior citizen for its performances.\r
\n" ); document.write( "\n" ); document.write( "On a recent event when 511 people paid admission the total receipts were $7020.\r
\n" ); document.write( "\n" ); document.write( " How many senior citizens attended the event??\r
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\n" ); document.write( "\n" ); document.write( " You must use a system of linear equations to solve; show all logic and work.
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Algebra.Com's Answer #725515 by ikleyn(52786) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "  a +   s =  511,     (1)     (counting adults \"a\" and senior citizens \"s\")\r\n" );
document.write( "20a + 10s = 7020.     (2)     (counting dollars).\r\n" );
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document.write( "Equations (1) and (2) form the system of two equations in two unknowns, \"a\" and \"s\".\r\n" );
document.write( "Use the Elimination method to solve the system.\r\n" );
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document.write( "For it, multiply eq(1) by 10 (both sides). You will get\r\n" );
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document.write( "10a + 10s = 5110,     (1')\r\n" );
document.write( "20a + 10s = 7020.     (2')\r\n" );
document.write( "------------------------------------ Now subtract eq(1') from eq(2') (both sides).\r\n" );
document.write( "                                     The terms \"10s\" will cancel each other,\r\n" );
document.write( "                                     And you will get a single equation for single unknown \"a\". \r\n" );
document.write( "                                     It is how the Elimination method works.\r\n" );
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document.write( "20a - 10a = 7020 - 5110 =  1910\r\n" );
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document.write( "10a = 1910  ====>  a =  = 191.\r\n" );
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document.write( "Answer.  191 adults and the rest 511 - 191 =  320 senior citizens.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.   //   On the way, you learned on how the Elimination method works.\r
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\n" ); document.write( "To see many other similar solved problems, look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Oranges and grapefruits \r
\n" ); document.write( "\n" ); document.write( "    - Using systems of equations to solve problems on tickets \r
\n" ); document.write( "\n" ); document.write( "    - Three methods for solving standard (typical) problems on tickets\r
\n" ); document.write( "\n" ); document.write( "    - Using systems of equations to solve problems on shares \r
\n" ); document.write( "\n" ); document.write( "    - Using systems of equations to solve problems on investment\r
\n" ); document.write( "\n" ); document.write( "    - Two mechanics work on a car \r
\n" ); document.write( "\n" ); document.write( "    - The Robinson family and the Sanders family each used their sprinklers last summer\r
\n" ); document.write( "\n" ); document.write( "    - Roses and vilolets \r
\n" ); document.write( "\n" ); document.write( "    - Counting calories and grams of fat in combined food\r
\n" ); document.write( "\n" ); document.write( "    - HOW TO algebreze and solve this problem on 2 equations in 2 unknowns \r
\n" ); document.write( "\n" ); document.write( "    - One unusual problem to solve using system of two equations \r
\n" ); document.write( "\n" ); document.write( "    - Solving mentally word problems on two equations in two unknowns \r
\n" ); document.write( "\n" ); document.write( "    - Solving systems of non-linear equations by reducing to linear ones \r
\n" ); document.write( "\n" ); document.write( "    - System of equations helps to solve a problem for the Thanksgiving day\r
\n" ); document.write( "\n" ); document.write( "    - Using system of two equations to solve the problem for the day of April, 1 \r
\n" ); document.write( "\n" ); document.write( "in this site.\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 \"Systems of two linear equations in two unknowns\".\r
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\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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