document.write( "Question 1111897: linda invested some money for one year in bonds that pay 8% simple interest and three times as much in preferred stock that earns 11% simple interest. if the total interest earned from the two investments was $1640, how much was invested in the bonds? \n" ); document.write( "

Algebra.Com's Answer #726928 by josmiceli(19441) $\"\"$ $\"About$

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Use simple interest formula
\n" ); document.write( " $\"+I+=+P%2Ar%2At+\"$
\n" ); document.write( "Let $\"+I+\"$ = interest earned from 8% investment
\n" ); document.write( " $\"+1640+-+I+\"$ = interest earned from 11% investment
\n" ); document.write( "Let $\"+P+\"$ = amount invested at 8%
\n" ); document.write( " $\"+3P+\"$ = amount invested at 11%
\n" ); document.write( "------------------------------------------
\n" ); document.write( "For 8% investment:
\n" ); document.write( "(1) $\"+I+=+P%2A.08%2A1+\"$
\n" ); document.write( "For 11% investment:
\n" ); document.write( "(2) $\"+1640+-+I+=+3P%2A.11%2A1+\"$
\n" ); document.write( "--------------------------------
\n" ); document.write( "(1) $\"+I+=+.08P+\"$
\n" ); document.write( "and
\n" ); document.write( "(2) $\"+1640+-+I+=+.33P+\"$
\n" ); document.write( "Plug (1) into (2)
\n" ); document.write( "(2) $\"+1640+-+.08P+=+.33P+\"$
\n" ); document.write( "(2) $\"+.41P+=+1640+\"$
\n" ); document.write( "(2) $\"+P+=+4000+\"$
\n" ); document.write( "and
\n" ); document.write( " $\"+3P+=+12000+\"$
\n" ); document.write( "------------------------
\n" ); document.write( "$4,000 was invested @ 8%
\n" ); document.write( "$12,000 was invested @ 11%
\n" ); document.write( " \n" ); document.write( "

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