document.write( "Question 518744: Susan had $20,000 to invest. She decided to invest part of it in a high-risk bond that yields 8.2% annual interest, and the rest in a savings bank yielding 3.9% per year. What least amount should she invest in the high-risk bond if she wants to receive at least $1,000 interest per year? \n" ); document.write( "
Algebra.Com's Answer #345250 by mananth(16946)\"\" \"About 
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Investment II 8.20% per annum ---x
\n" ); document.write( "Investment II 3.90% per annum ---y
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\n" ); document.write( "x + y= 20000 ------------------------1
\n" ); document.write( "8.20% x + 3.90% y= = $1,000.00
\n" ); document.write( "Multiply by 100
\n" ); document.write( "8.2 x + 3.9 y= = $100,000.00 --------2
\n" ); document.write( "
\n" ); document.write( "Multiply (1) by -8.2
\n" ); document.write( "we get
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\n" ); document.write( "-8.2 x -8.2 y= = -164000.00
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\n" ); document.write( "Add this to (2)
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\n" ); document.write( "0 x -4.3 y= = -$64,000.00
\n" ); document.write( "
\n" ); document.write( "divide by -4.3
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\n" ); document.write( " y = $14,883.72 investment at
\n" ); document.write( "Balance $5,116.28 investment at
\n" ); document.write( "CHECK
\n" ); document.write( "$5,116.28 --------- 8.20% ------- $419.53
\n" ); document.write( "$14,883.72 ------- 3.90% ------- $580.47
\n" ); document.write( "Total ------- $1,000.00
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