document.write( "Question 1122749: Jerome had $18,000 to invest. He put some of the money in an account earning 3% simple interest, and the rest in a CD earning 8% simple interest. At the end of the year he had $1190 in total interest, how much did he invest at each rate? \n" ); document.write( "

Algebra.Com's Answer #738909 by ikleyn(52866) $\"\"$ $\"About$

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document.write( "Let x = amount at 8%, in dollars.\r\n" );
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document.write( "Then the amount at 3% is the rest (18000-x) dollars.\r\n" );
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document.write( "The interest from the 8% amount is 0.08*x  dollars.\r\n" );
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document.write( "The interest from the 3%   amount is 0.03*(18000-x)   dollars.\r\n" );
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document.write( "Your equation is\r\n" );
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document.write( "    interest + interest       = total interest,   or\r\n" );
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document.write( "    0.08*x   + 0.03*(18000-x) = 1190   dollars.\r\n" );
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document.write( "    x =  = 13000.\r\n" );
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document.write( "Answer.  The amount at 8% is $13000;  the rest  $18000-$13000 = $5000 is the amount at 3%.\r\n" );
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document.write( "Check.   0.03*5000 + 0.08*13000 = 11900 dollars.   ! Correct !\r\n" );
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\n" ); document.write( "\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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