document.write( "Question 1105498: Natasha invests $2100 in one account and $1400 in an account paying 2 % higher interest. At the end of one year she had earned $168 in interest. At what rates did she invest?\r
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Algebra.Com's Answer #720343 by ikleyn(52787) $\"\"$ $\"About$

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document.write( "Interest + interest      = total interest\r\n" );
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document.write( "2100*x   + 1400*(x+0.02) = 168    <<<---=== where x is percentage for $2100 loan expressed as the decimal (like 3.5% = 0.0035 . . . )\r\n" );
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document.write( "2100x + 1400x + 28 = 168\r\n" );
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document.write( "3500x = 168 - 28 = 140  ====>  x =  = 0.04 = 4%.\r\n" );
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document.write( "Answer.  $2100 was invested at 4%  and  $1400 was invested at 6%.\r\n" );
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document.write( "Check.   2100*0.04 + 1400*0.06 = 168 dollars.   ! Correct !\r\n" );
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