document.write( "Question 419077: Dave Horn invested half of his money at 5%, one-tird of his money at4%, and the rest at 3.5%. If his total annual investment incomw is $530, how much had he invested? \n" ); document.write( "

Algebra.Com's Answer #853233 by ikleyn(53427) $\"\"$ $\"About$

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\n" ); document.write( "Dave Horn invested half of his money at 5%, one-tird of his money at4%, and the rest at 3.5%.
\n" ); document.write( "If his total annual investment income is $530, how much had he invested?
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\n" ); document.write( "\n" ); document.write( "        @mananth incorrectly interpreted the problem and incorrectly treated it.\r
\n" ); document.write( "\n" ); document.write( "        Therefore, his solution and his answer both are incorrect.\r
\n" ); document.write( "\n" ); document.write( "        I came to bring a correct solution.\r
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document.write( "percent    part   \r\n" );
document.write( "  5        1/2\r\n" );
document.write( "  4        1/3\r\n" );
document.write( "  3.5      the rest = 1 - 1/2 - 1/3 = 1 - 5/6 = 1/6\r\n" );
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document.write( "Let x be the total investment.\r\n" );
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document.write( "Write an equation for the total interest\r\n" );
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document.write( "     +  +  = 530 dollars.\r\n" );
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document.write( "It is your setup equation.  Now you should find the unknown x from it.\r\n" );
document.write( "For it, first multiply this equation by 6 to rid the denominators.  You will get\r\n" );
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document.write( "    0.05*(3x) + 0.04*(2x) + 0.035x = 6*530,\r\n" );
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document.write( "    0.15x + 0.08x + 0.035x = 3180.\r\n" );
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document.write( "            0.265x         = 3180,\r\n" );
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document.write( "                 x         = 3180/0.265 = 12000.\r\n" );
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document.write( "ANSWER.  $6000 was invested at 5%;  $4000 was invested at 4%,  and  $2000 was invested at 3.5%.\r\n" );
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document.write( "CHECK.  0.05*6000 + 0.04*4000 + 0.035*2000 = 530  dollars.   ! correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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