document.write( "Question 397688: Last year Maria invested $10,000, part at 6% annual interest and the rest at 8% annual interest. if she received $760 in interest at the end of the year, how much dis she invest at each rate? \n" ); document.write( "

Algebra.Com's Answer #281770 by stanbon(75887) $\"\"$ $\"About$

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Last year Maria invested $10,000, part at 6% annual interest and the rest at 8% annual interest. if she received $760 in interest at the end of the year, how much dis she invest at each rate?
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\n" ); document.write( "Quantity Eq: x + y = 10,000
\n" ); document.write( "Interest Eq:0.06x+0.08y = 760
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\n" ); document.write( "Multiply thru 1st Eq. by 6
\n" ); document.write( "Multiply thru 2nd Eq. by 100
\n" ); document.write( "-------
\n" ); document.write( "6x + 6y = 6*10000
\n" ); document.write( "6x + 8y = 76000
\n" ); document.write( "---------------
\n" ); document.write( "Subtract 1st equation from 2nd and solve for \"y\":
\n" ); document.write( "2y = 16000
\n" ); document.write( "y = $8000 (amt. invested at 8%)
\n" ); document.write( "----
\n" ); document.write( "Solve for \"y\":
\n" ); document.write( "x + y = 10,000
\n" ); document.write( "x + 8000 = 10,000
\n" ); document.write( "x = $2000 (amt. invested at 6%)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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