document.write( "Question 503345: A total of $3900 was invested, part of it at 8% interest and the remainder at 13%. If the total yearly interest amounted to $395, how much was invested at each rate? \n" ); document.write( "

Algebra.Com's Answer #339195 by mananth(16946) $\"\"$ $\"About$

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Investment I 8.00% per annum ---x
\n" ); document.write( "Investment II 13.00% per annum ---y
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\n" ); document.write( "x + y= 3900 ------------------------1
\n" ); document.write( "8.00% x + 13.00% y = $395.00
\n" ); document.write( "Multiply by 100
\n" ); document.write( "8 x + 13 y = $39,500.00
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\n" ); document.write( "Multiply (1) by -8
\n" ); document.write( "we get
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\n" ); document.write( "-8 x -8 y = -31200.00
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\n" ); document.write( "Add this to (2)
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\n" ); document.write( "0 x +5 y = $8,300.00
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\n" ); document.write( "divide by 5
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\n" ); document.write( " y = $1,660.00
\n" ); document.write( "Balance $2,240.00
\n" ); document.write( "CHECK
\n" ); document.write( "$2,240.00 --------- 8.00% ------- $179.20
\n" ); document.write( "$1,660.00 ------- 13.00% ------- $215.80
\n" ); document.write( "Total ------- $395.00
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