document.write( "Question 557815: A man invested $100,000. Part of it is invested at 10% and the rest at 8%. If the total income is $8800, how mush did he invest at 10%? \n" ); document.write( "

Algebra.Com's Answer #362786 by mananth(16946) $\"\"$ $\"About$

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Investment I 10.00% per annum ----x
\n" ); document.write( "Investment II 8.00% per annum ----y
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\n" ); document.write( "x+y= 100000 ------------------------1
\n" ); document.write( "10.00% x+8.00% y=$8,800.00
\n" ); document.write( "Multiply by 100
\n" ); document.write( "10x+8y= $880,000.00 --------2
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\n" ); document.write( "Multiply (1) by -10
\n" ); document.write( "we get
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\n" ); document.write( "-10x-10 y =-1000000.00
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\n" ); document.write( "Add this to (2)
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\n" ); document.write( "-2 y = -$120,000.00
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\n" ); document.write( "divide by -2
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\n" ); document.write( "y = $60,000.00 investment at 8.00%
\n" ); document.write( "Balance $40,000.00 investment at 10.00%
\n" ); document.write( "CHECK
\n" ); document.write( "$40,000.00 $4,000.00
\n" ); document.write( "$60,000.00 $4,800.00
\n" ); document.write( "Total $8,800.00
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