document.write( "Question 618298: A mother wants to invest $11,000.00 for her son's future education. She invests a portion of the money in a bank certificate of deposit (CD account) which earns 4% and the remainder in a savings bond that earns 7%. If the total interest earned after one year is $660.00. How much money was invested in the CD account \n" ); document.write( "
Algebra.Com's Answer #388829 by mananth(16946)\"\" \"About 
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CD 4.00% per annum ------------- Amount invested =x
\n" ); document.write( "Savings bond 7.00% per annum ------------ Amount invested = y
\n" ); document.write( " 11000
\n" ); document.write( "Interest----- 660
\n" ); document.write( "
\n" ); document.write( "CD 4.00% per annum ---x
\n" ); document.write( "Savings bond 7.00% per annum ---y
\n" ); document.write( "Sum of investments
\n" ); document.write( "x + y= 11000 -------------1
\n" ); document.write( "Interest earned on both investments
\n" ); document.write( "4.00% x + 7.00% y= 660
\n" ); document.write( "Multiply by 100
\n" ); document.write( "4 x + 7 y= 66000.00 --------2
\n" ); document.write( "Multiply (1) by -4
\n" ); document.write( "we get
\n" ); document.write( "-4 x -4 y= -44000.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x 3 y= 22000
\n" ); document.write( "divide by 3
\n" ); document.write( " y = 7333.33
\n" ); document.write( "CD 7.00% $ 7333.33
\n" ); document.write( "Savings bond 4.00% $ 3666.67
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "7333.33 --------- 7.00% ------- 513.33
\n" ); document.write( "3666.67 ------------- 4.00% ------- 146.67
\n" ); document.write( "Total -------------------- 660.00
\n" ); document.write( "
\n" ); document.write( "m.ananth@hotmail.ca
\n" ); document.write( " \n" ); document.write( "
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