document.write( "Question 1151867: Rachel invested $9000 in money market funds, part at 6% and the rest at 4.5% annual interest. after one year, she earned $ 480.75 in interest. How much was invested at each rate? \n" ); document.write( "
Algebra.Com's Answer #773732 by ikleyn(52778)\"\" \"About 
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document.write( "x dollars invested at 6% and the rest, (9000-x) dollars invested at 4.5%.\r\n" );
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document.write( "The total interest is the sum of partial interest.\r\n" );
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document.write( "In the equation form it is\r\n" );
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document.write( "    0.06x + 0.045*(9000-x) = 480.75  dollars.\r\n" );
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document.write( "From the equation,  \r\n" );
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document.write( "    x = \"%28480.75+-+0.045%2A9000%29%2F%280.06-0.045%29\" = 5050  dollars.\r\n" );
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document.write( "ANSWER.  $5050 invested at 6%  and the rest,  9000-5050 = 3950  dollars invested at 4.5%.\r\n" );
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document.write( "CHECK.   0.06*5050 + 0.045*3950 = 480.75 dollars.   ! Precisely correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "Every day we solve 3 - 5 similar problems at this forum.\r
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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( "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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