document.write( "Question 1044180: An executive invests $30,000, some at 10% and some at 5%. If she receives an annual return of $2,200, how much is invested at 10%? \n" ); document.write( "

Algebra.Com's Answer #659440 by ikleyn(52794) $\"\"$ $\"About$

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\n" ); document.write( "An executive invests $30,000, some at 10% and some at 5%. If she receives an annual return of $2,200, how much is invested at 10%?
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\n" ); document.write( "\n" ); document.write( "1. Solution with two unknowns\r
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document.write( "Let t be an amount invested at 10%, and f be an amount invested at 5%. Then you have these to equations\r\n" );
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document.write( "   t +     f = 30000,\r\n" );
document.write( "0.1t + 0.05f = 2200.\r\n" );
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document.write( "You can solve it by the substitution method or by the elimination method.\r\n" );
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\n" ); document.write( "\n" ); document.write( "2. Solution with one unknown\r
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document.write( "Then your equation is \r\n" );
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document.write( "0.1t + 0.05*(30000-t) = 2200,   or\r\n" );
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document.write( "0.1t + 5*300 - 0.05t = 2200,   or\r\n" );
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document.write( "0.05t = 2200-1500,   or\r\n" );
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document.write( "0.05t = 700,   t =  = 14000.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Answer. 14000 invested at 10%, 16000 invested at 5%.\r
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