document.write( "Question 189886: Mike invested $7000 for one year. He invested part of it at 8% and the rest at 12%. At the end of the year he earned $764 in interest. How much did he invest at each rate? Can someone help me solve this problem I am confused. \n" ); document.write( "

Algebra.Com's Answer #142528 by jojo14344(1513) $\"\"$ $\"About$

You can put this solution on YOUR website!

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\n" ); document.write( "Let x = amount invested at 8%
\n" ); document.write( "And, $7,000 - x = amount inv. at 12%\r
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\n" ); document.write( "\n" ); document.write( "Adding both to earn $764 interest:\r
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\n" ); document.write( "\n" ); document.write( " $\"0.08%28x%29%2B0.12%287000-x%29=764\"$
\n" ); document.write( " $\"0.08x%2B840-0.12x=764\"$
\n" ); document.write( "Combine similar terms: (change signs, \"+\" or \"-\")
\n" ); document.write( " $\"840-764=0.12x-0.08x\"$
\n" ); document.write( " $\"76=0.04x\"$ ----> $\"cross%2876%291900%2Fcross%280.04%29=cross%280.04%29x%2Fcross%280.04%29\"$
\n" ); document.write( "x= $1,900.00 amount inv. at 8%\r
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\n" ); document.write( "\n" ); document.write( "$7,000.00 - $1,900.00 = $5,100.00, amount inv. at 12%\r
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\n" ); document.write( "\n" ); document.write( "Let us check,
\n" ); document.write( " $\"0.08%281900%29%2B0.12%285100%29=764\"$
\n" ); document.write( " $\"152%2B612=764\"$
\n" ); document.write( " $\"764=764\"$ \r
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\n" ); document.write( "\n" ); document.write( "*Note: It's just make sense to invest more on higher interest\r
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\n" ); document.write( "\n" ); document.write( "Thank you,
\n" ); document.write( "Jojo \n" ); document.write( "

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