document.write( "Question 1114410: mr. smith invests part of $8000 at 4% and the remainder at 6%. the annual effective rate on his total investment is 4.4%. find the amount invested at each rate. \n" ); document.write( "

Algebra.Com's Answer #729348 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "0.04*x + 0.06*(8000-x) = 0.044*8000\r\n" );
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document.write( "0.04x + 480 - 0.06x = 0.044*8000\r\n" );
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document.write( "-0.02x = 0.044*8000 - 480 = -128  ====>  x =  = 6400.\r\n" );
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document.write( "Answer.  $6400 was invested at 4%  and the rest  (8000-6400) = 1600 was invested at 6%.\r\n" );
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document.write( "Check.   0.04*6400 + 0.06*1600 = 352 dollars.\r\n" );
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document.write( "         8000*0.044 = 352 dollars,  the same value.    ! Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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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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