document.write( "Question 141980: What if the interest earned by $8000 invested at a certain rate is $500 less than $12000 would earn at a rate 1% lower, at what rate is $8000 invested? \n" ); document.write( "
Algebra.Com's Answer #103435 by ankor@dixie-net.com(22740)\"\" \"About 
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What if the interest earned by $8000 invested at a certain rate is $500 less than $12000 would earn at a rate 1% lower, at what rate is $8000 invested?
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\n" ); document.write( "Let x = rate (in decimals) that $8000 is invested
\n" ); document.write( "then
\n" ); document.write( "(x-.01) = rate that $12000 is invested
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\n" ); document.write( "A simple equation:
\n" ); document.write( "int at 12k = int at 8k + 500
\n" ); document.write( ":
\n" ); document.write( "12000(x-.01) = 8000x + 500
\n" ); document.write( ":
\n" ); document.write( "12000x - 120 = 8000x + 500
\n" ); document.write( ":
\n" ); document.write( "12000x - 8000x = 500 + 120
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\n" ); document.write( "4000x = 620
\n" ); document.write( "x = \"620%2F4000\"
\n" ); document.write( "x = .155 which is 15.5% interest rate of the $8000
\n" ); document.write( ":
\n" ); document.write( "Check solution by finding the interest of each amt: (12k int = 14.5%)
\n" ); document.write( ".145 * 12000 = 1740
\n" ); document.write( ".155 * 8000 = 1240
\n" ); document.write( "-------------------
\n" ); document.write( "the difference: 500 \n" ); document.write( "
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