document.write( "Question 1166530: A retired couple has $192,000 to invest. A safe investment yields 9.5% per year, but a riskier investment yields 12.5% per year. How much should they invest at each rate to earn $21,000 per year? \n" ); document.write( "

Algebra.Com's Answer #791054 by ikleyn(52776) $\"\"$ $\"About$

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document.write( "Let x be the 12.5% investment.\r\n" );
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document.write( "Then the other investment is (192000-x) dollars,\r\n" );
document.write( "and you have this equation for the total interest\r\n" );
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document.write( "    0.125x + 0.095*(192000-x) = 21000  dollars.\r\n" );
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document.write( "From the equation,\r\n" );
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document.write( "    x =  = 92000  dollars.\r\n" );
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document.write( "ANSWER.  $92000 invested at 12.5% and the rest,  192000-92000 = 100000  dollars invested at  9.5%.\r\n" );
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document.write( "CHECK.   0.125*92000 + 0.095*100000 = 21000 total interest.   ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "It is a standard and typical problem on investments.\r
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\n" ); document.write( "\n" ); document.write( "If you need more details, or if you want to see other similar problems solved by different methods, look into the lesson \r
\n" ); document.write( "\n" ); document.write( " - Using systems of equations to solve problems on investment\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "You will find there different approaches (using one equation or a system of two equations in two unknowns), as well as
\n" ); document.write( "different methods of solution to the equations (Substitution, Elimination).\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 lesson is 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( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\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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