document.write( "Question 283771: Kevin invested part of his 10,000 bonus in a certificate of deposit that paid 6% annual simple interest, and the remainder in a mutual fund that paid 11% annual simple interest. If his total interest for that year was $900, how much did kevin invest in the mutual fund? \n" ); document.write( "

Algebra.Com's Answer #854223 by ikleyn(53878) $\"\"$ $\"About$

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\n" ); document.write( "Kevin invested part of his 10,000 bonus in a certificate of deposit that paid 6% annual simple interest,
\n" ); document.write( "and the remainder in a mutual fund that paid 11% annual simple interest.
\n" ); document.write( "If his total interest for that year was $900, how much did Kevin invest in the mutual fund?
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\n" ); document.write( "\n" ); document.write( " The solution in the post by @mananth is incorrect, leading to wrong answer.\r
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document.write( "Let x be the amount invested at 11%.\r\n" );
document.write( "Then the amount invested at 6% is (10000-x).\r\n" );
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document.write( "Write the annual interest equation\r\n" );
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document.write( "    0.11x + 0.06*(10000-x) = 900.\r\n" );
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document.write( "Simplify and find x\r\n" );
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document.write( "    0.11x + 600 - 0.06x = 900,\r\n" );
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document.write( "    0.11x - 0.06x = 900 - 600,\r\n" );
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document.write( "          0.05x   =     300\r\n" );
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document.write( "              x   =     300/0.05 = 6000.\r\n" );
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document.write( "ANSWER.  Kevin invested  $6000 in the mutual fund.\r\n" );
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document.write( "CHECK.  The total annual interest was  0.11*6000 + 0.06*(10000-6000) = 900 dollars,\r\n" );
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document.write( "        which is precisely correct.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved correctly.\r
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