document.write( "Question 1120806: Rodrigo invests $4000, part of it at 10% annual interest and the rest at 12% annual interest. If he receives $460 in interest at the end of one year, how much did he invest at each rate? \n" ); document.write( "

Algebra.Com's Answer #736684 by ikleyn(52790) $\"\"$ $\"About$

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document.write( "Equation:\r\n" );
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document.write( "interest  + interest      = 460\r\n" );
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document.write( "0.10*x    + 0.12*(4000-x) = 460\r\n" );
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document.write( "Simplify and solve for x:\r\n" );
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document.write( "10x + 12*4000 - 12x = 460*100\r\n" );
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document.write( "-2x = 46000 - 12*4000\r\n" );
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document.write( "x      =  =  1000 dollars  (amount invested at 10%)\r\n" );
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document.write( "4000-x = 3000 dollars  (amount invested at 12%)\r\n" );
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document.write( "Check.  0.10*1000 + 0.12*3000 = 460  dollars.   ! Correct !\r\n" );
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document.write( "Answer.  $1000 invested at 10% and $3000 invested at 12%.\r\n" );
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\n" ); document.write( "It is a typical and standard problem on investment.\r
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\n" ); document.write( "\n" ); document.write( "To see many other similar solved problems on investment, 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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