document.write( "Question 1138527: Mr. Lopez has two sums of money earning interests, one at 3%, the other at 4%. His annual income from the two investment is 410 pesos. If he could get 4% on all of his money this income would be 480 pesos. How much did he invest at each rate? \n" ); document.write( "

Algebra.Com's Answer #756326 by ikleyn(52817) $\"\"$ $\"About$

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document.write( "If he could get 4% on ALL of his money, his income would be 480 pesos.\r\n" );
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document.write( "It means that the total of two investments is   = 12000 pesos.\r\n" );
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document.write( "Let x = amount at 3%, in pesos.\r\n" );
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document.write( "Then the amount at 4% is the rest (12000-x) pesos.\r\n" );
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document.write( "The interest from the 3% amount is 0.03*x  pesos.\r\n" );
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document.write( "The interest from the 4%   amount is 0.04*(12000-x)   pesos.\r\n" );
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document.write( "Your equation is\r\n" );
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document.write( "    interest + interest      = total interest,   or\r\n" );
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document.write( "    0.03*x  + 0.04*(12000-x) = 410   pesos.\r\n" );
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document.write( "From the equation, express x and calculate the answer\r\n" );
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document.write( "    x =  = 7000.\r\n" );
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document.write( "Answer.  The amount at 3% is $7000;  the rest  $12000-$7000 = $5000 is the amount at 4%.\r\n" );
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document.write( "Check.   0.03*7000 + 0.04*5000 = 410 pesos.   ! 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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