document.write( "Question 105784: Carla invested $28,000, part at 14% and part at 9%. If the total interest at the end of the year is $3,370, how much did she invest at 14%? \n" ); document.write( "

Algebra.Com's Answer #76985 by Fombitz(32388) $\"\"$ $\"About$

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F-amount invested at 14%
\n" ); document.write( "N-amount invested at 9%
\n" ); document.write( "Total amount = F + N = $28000
\n" ); document.write( "1. $\"F%2BN=28000\"$
\n" ); document.write( "Interest at 14% plus Interest at 9% = Total interest = $3370.
\n" ); document.write( "2. $\"0.14%2AF%2B0.09%2AN=3370\"$
\n" ); document.write( "Use equation 1. to solve for F in terms of N,
\n" ); document.write( "1. $\"F%2BN=28000\"$
\n" ); document.write( " $\"F=28000-N\"$
\n" ); document.write( "Substitute your result into equation 2.
\n" ); document.write( "2. $\"0.14%2AF%2B0.09%2AN=3370\"$
\n" ); document.write( " $\"0.14%2A%2828000-N%29%2B0.09%2AN=3370\"$
\n" ); document.write( " $\"0.14%2A%2828000%29-0.14N%2B0.09%2AN=3370\"$
\n" ); document.write( " $\"3920-0.05%2AN=3370\"$
\n" ); document.write( " $\"-0.05%2AN=3370-3920\"$
\n" ); document.write( " $\"-0.05%2AN=-550\"$
\n" ); document.write( " $\"N=%28-550%29%2F%28-0.05%29\"$
\n" ); document.write( " $\"highlight%28N=11000%29\"$
\n" ); document.write( " $\"F=28000-N\"$
\n" ); document.write( " $\"F=28000-11000\"$
\n" ); document.write( " $\"highlight%28F=17000%29\"$
\n" ); document.write( "Check your answer.
\n" ); document.write( "1. $\"F%2BN=28000\"$
\n" ); document.write( " $\"17000%2B11000=280000\"$
\n" ); document.write( " $\"28000=28000\"$
\n" ); document.write( "Good answer.
\n" ); document.write( "2. $\"0.14%2AF%2B0.09%2AN=3370\"$
\n" ); document.write( " $\"0.14%2A17000%2B0.09%2A11000=3370\"$
\n" ); document.write( " $\"2380%2B990=3370\"$
\n" ); document.write( " $\"3370=3370\"$
\n" ); document.write( "Good answer.
\n" ); document.write( "$17,000 at 14% and $11,000 at 9%. \n" ); document.write( "

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