document.write( "Question 1108701: Walt made an extra $7000 last year from a part-time job. He invested part of the money at 6% and the rest at 8%. He made a total of $480 in interest. How much was invested at 8%? \n" ); document.write( "
Algebra.Com's Answer #723714 by ikleyn(52814)\"\" \"About 
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\n" ); document.write( "Walt made an extra $7000 last year from a part-time job. He invested part of the money at 6% and the rest at 8%.
\n" ); document.write( "He made a total of $480 in interest. How much was invested at 8%?
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document.write( "Interest at 8%  +  interest at 6% = total interest\r\n" );
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document.write( "0.08*x          +  0.06*(7000-x)  = 480\r\n" );
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document.write( "0.08x + 420 - 0.06x = 480\r\n" );
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document.write( "0.02x = 480 - 420  ====>  0.02x = 60  ====>  x [ \"60%2F0.02\" = \"6000%2F2\" = 3000.\r\n" );
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document.write( "Answer.  $3000 was invested at 8%.\r\n" );
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document.write( "Check.   0.08*3000 + 0.06*(7000-3000) = 480 dollars.   ! Correct !\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( "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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