document.write( "Question 399228: Michael has $12,500 to invest. He invests part in an account which earns 4.2% annual interest and the rest in an account which earns 6.2% annual interest. He earns $669.50 in interest at the end of the year. How much was invested at each rate? \n" ); document.write( "
Algebra.Com's Answer #282714 by stanbon(75887)\"\" \"About 
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Michael has $12,500 to invest. He invests part in an account which earns 4.2% annual interest and the rest in an account which earns 6.2% annual interest. He earns $669.50 in interest at the end of the year. How much was invested at each rate?
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\n" ); document.write( "Equations:
\n" ); document.write( "Quantity Eq.:: x + y = 12,500
\n" ); document.write( "Interest Eq.::0.042x + 0.062y = 669.50
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\n" ); document.write( "Multiply thru Quantity by 42.
\n" ); document.write( "Multiply thru Interest by 1000.
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\n" ); document.write( "42x + 42y = 42*12,500
\n" ); document.write( "42x + 62y = 669500
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\n" ); document.write( "Subtract 1st from 2nd and solve for \"y\":
\n" ); document.write( "20y = 144500
\n" ); document.write( "y = $7225 (amt. invested at 6.2%
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\n" ); document.write( "Solve for \"x\":
\n" ); document.write( "x+ y = 12,500
\n" ); document.write( "x + 7225 = 12,500
\n" ); document.write( "x = $5275 (amt. invested at 4.2%)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H. \n" ); document.write( "
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