document.write( "Question 420200: jonathan invested a total of $3200, part at 4% simple interest and part at 5% simple interest. at the end of 1 year, the investments earned $145 interest. how much was invested at each rate? \n" ); document.write( "

Algebra.Com's Answer #293674 by mananth(16946) $\"\"$ $\"About$

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4.00% per annum------------- x
\n" ); document.write( "5.00% per annum------------ y
\n" ); document.write( "total investment 3200
\n" ); document.write( "Interest----- $145.00
\n" ); document.write( "....
\n" ); document.write( "x + y 3200 ------------------------1
\n" ); document.write( "4.00% x + 5.00% y = $145.00
\n" ); document.write( "Multiply by 100
\n" ); document.write( "4 x + 5 y = $14,500.00 --------2
\n" ); document.write( "
\n" ); document.write( "Multiply (1) by -4
\n" ); document.write( "we get
\n" ); document.write( "
\n" ); document.write( "-4 x -4 y = -12800
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\n" ); document.write( "Add this to (2) we get
\n" ); document.write( "
\n" ); document.write( "y = $1,700.00
\n" ); document.write( "
\n" ); document.write( "y =$1,700.00 investment at 5.00%
\n" ); document.write( "Balance $1,500.00 investment at 4.00%
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