document.write( "Question 225520: Robert invests $8000 in a bank. Part is invested at 7% simple interest and part at 9% simple interest. In one year Robert earns $660 in interest. How much did he invest at each amount? \n" ); document.write( "

Algebra.Com's Answer #168248 by solver91311(24713) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "Let

represent the amount invested at 7%. Then the amount invested at 9% must be

. The amount of interest earned on the 7% investment is then

and the amount earned on the 9% investment is

. The sum of these two amounts earned is $660, so:\r
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\n" ); document.write( "\n" ); document.write( "Solve for

to get the amount at 7% and subtract that amount from 8000 to get the other amount.\r
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\n" ); document.write( "\n" ); document.write( "John
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