document.write( "Question 853703: The annual interest rate on a $14000 investment exceeds the interest on a $7000 investment by $672. The $14000 is invested at a 0.3% higher rate of interest than the $7000 . what is the interest rate if each investment? \n" ); document.write( "
Algebra.Com's Answer #514207 by mananth(16946)\"\" \"About 
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The annual interest on a $14000 investment exceeds the interest on a $7000 investment by $672. The $14000 is invested at a 0.3% higher rate of interest than the $7000 . what is the interest rate if each investment?\r
\n" ); document.write( "\n" ); document.write( "Let interest rate of $14000 be x%\r
\n" ); document.write( "\n" ); document.write( "and Interest rate for $7000 be y %\r
\n" ); document.write( "\n" ); document.write( "According to the first condition\r
\n" ); document.write( "\n" ); document.write( "14000 *x% - 7000*y% = 672
\n" ); document.write( "multiply by 100
\n" ); document.write( "14000x-7000y = 67200
\n" ); document.write( "/700
\n" ); document.write( "20x-10y=96.................(1)\r
\n" ); document.write( "\n" ); document.write( "II condition
\n" ); document.write( "x%=y%+0.3%
\n" ); document.write( "x=y+0.3
\n" ); document.write( "x-y=0.3..................................(2)\r
\n" ); document.write( "\n" ); document.write( "solve (1) & (2)\r
\n" ); document.write( "\n" ); document.write( "20 x -10 y = 96 .............1
\n" ); document.write( "Total value
\n" ); document.write( "1 x -1 y = 0.30 .............2
\n" ); document.write( "Eliminate y
\n" ); document.write( "multiply (1)by 1
\n" ); document.write( "Multiply (2) by -10
\n" ); document.write( "20.00 x -10.00 y = 96.00
\n" ); document.write( "-10.00 x + 10.00 y = -3.00
\n" ); document.write( "Add the two equations
\n" ); document.write( "10.00 x = 93.00
\n" ); document.write( "/ 10.00
\n" ); document.write( "x = 9.30
\n" ); document.write( "plug value of x in (1)
\n" ); document.write( "20.00 x -10.00 y = 96.00
\n" ); document.write( "186.00 -10.00 y = 96.00
\n" ); document.write( " -10.00 y = 96.00 -186.00
\n" ); document.write( " -10.00 y = -90.00
\n" ); document.write( " y = 9.00
\n" ); document.write( "x= 9.30 Interest rate on $14000
\n" ); document.write( "y= 9.00 Interest rate on $7000
\n" ); document.write( "m.ananth@hotmail.ca \r
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