document.write( "Question 840882: margaret fennell won a prize for her work. she invested part of the money in a certificate of deposit at 4% and $3000 more than that amount in a bond paying 6%. her annual interest income was $780. how much did margaret invest in each rate? \n" ); document.write( "
Algebra.Com's Answer #506473 by hamsanash1981@gmail.com(151)\"\" \"About 
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Let the investment amount at 4% interest be x, then amount invested in a bond paying 6% will be x + 3000.
\n" ); document.write( "no of years = 1
\n" ); document.write( "Simple interest of deposit at 4% = (x * 1* 4)/100 => 4x/100
\n" ); document.write( "Simple interest of deposit at 6% = ((x+3000)* 1* 6)/100 => (6x+18000)/100
\n" ); document.write( "Total interest = 780
\n" ); document.write( "4x/100 + (6x+18000)/100 = 780
\n" ); document.write( "4x +6x +18000 = 78000
\n" ); document.write( "10x = 60000
\n" ); document.write( "x = 6000\r
\n" ); document.write( "\n" ); document.write( "therefore amount invested at 4% is 6000 and amount invested at 6% is 9000
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