document.write( "Question 1111872: a machinist invested $15,000, part at 6% simple interest and the remainder at 4% simple interest for one year. how much was invested at each rate if each investment earned the same interest? \n" ); document.write( "

Algebra.Com's Answer #726905 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Let  x  be the amount invested at 6%  (in dollars).\r\n" );
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document.write( "Then the remainder investment is (15000-x) dollars.\r\n" );
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document.write( "Next, write this equation\r\n" );
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document.write( "interest = interest    (as the condition states !)\r\n" );
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document.write( "0.06x    = 0.04*(15000-x)\r\n" );
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document.write( "0.06x = 0.04*15000 - 0.04x\r\n" );
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document.write( "0.06x + 0.04x = 0.04*15000\r\n" );
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document.write( "0.1x = 0.04*15000  ====>  x =  = 6000.\r\n" );
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document.write( "Answer.  $6000 was invested at 6%.  The rest,  15000-6000 = 9000 dollars was invested at 4%.\r\n" );
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document.write( "Check.   0.06*6000 = 360 dollars.\r\n" );
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document.write( "         0.04*9000 = 360 dollars.   ! The same value !  Solved correctly !\r\n" );
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\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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\n" ); document.write( "\n" ); document.write( "In this case, please refer to the problem ID number 1111872.\r
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\n" ); document.write( "\n" ); document.write( "Thank you. \r
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