document.write( "Question 1142768:
\n" ); document.write( "Suppose that you received an unexpected inheritance of $36,000. You have decided to invest the money by placing some of the money in stocks that pay 4.4% and the rest in bonds that pay 6%. How much should you place in each investment in order to earn 5%, or $1800 annually? \n" ); document.write( "

Algebra.Com's Answer #763500 by ikleyn(52864) $\"\"$ $\"About$

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document.write( "Let x = the amount invested at 4.4% and y = the amount invested at 6%.\r\n" );
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document.write( "Then from the condition you have these two equations in two unknowns\r\n" );
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document.write( "         x +     y = 36000  dollars    (1)    (total investment)\r\n" );
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document.write( "    0.044x + 0.06y =  1800  dollars    (2)    (total interest)\r\n" );
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document.write( "Solve the system by the Substitution method.\r\n" );
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document.write( "For it, from equation (1) express x = 36000 - y  and substitute it into equation (2). You will get\r\n" );
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document.write( "    0.044*(36000-y) + 0.06y = 1800\r\n" );
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document.write( "Simplify and express y from the last equation; then calculate\r\n" );
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document.write( "    y =  = 13500.\r\n" );
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document.write( "To find x, substitute the found value of y into equation (1). You will get then\r\n" );
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document.write( "    x = 36000 - 13500 = 22500.\r\n" );
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document.write( "ANSWER.  $22500 was invested at 4.4%  and  $13500 was invested at 6%.\r\n" );
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document.write( "CHECK.   0.044*22500 + 0.06*13500 = 1800  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
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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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