document.write( "Question 1121631: An executive invests $25,000, some at 8% and the rest at 6% annual interest. If he receives an annual return of $1,780, how much is invested at each rate? \n" ); document.write( "

Algebra.Com's Answer #737583 by ikleyn(52786) $\"\"$ $\"About$

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document.write( "Let x be an amount invested at  8%, in dollars.\r\n" );
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document.write( "Then the amount invested at  6%  was  (25000-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\r\n" );
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document.write( "    0.08*x   + 0.06*(25000-x) = 1780   dollars.\r\n" );
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document.write( "Simplify and solve for x:\r\n" );
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document.write( "    0.08x + 0.06*25000 - 0.06x = 1780\r\n" );
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document.write( "    0.02x = 1780 - 0.06*2500 = 280  ====>  x =  = 14000.\r\n" );
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document.write( "Answer.  $14000 was invested at 8%.  The rest  $25000 - $14000 = $11000 was invested at 6%.\r\n" );
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document.write( "Check.   0.08*14000 + 0.06*11000 = 1780 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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