document.write( "Question 724448: An investor invested a total of $1700 in two mutual funds. One fund earned 9% profit while the other earned a 7% profit. If the investor's total profit was $131, how much was invested in each mutual fund?\r
\n" ); document.write( "\n" ); document.write( "The amount invested in the mutual fund that earned 9% was?
\n" ); document.write( "The amount invested in the mutual fund that earned 7% was? \n" ); document.write( "
Algebra.Com's Answer #443743 by mananth(16946)\"\" \"About 
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Part I 9.00% per annum ------------- Amount invested =x
\n" ); document.write( "Part II 7.00% per annum ------------ Amount invested = y
\n" ); document.write( " 1700
\n" ); document.write( "Interest----- 131
\n" ); document.write( "
\n" ); document.write( "Part I 9.00% per annum ---x *
\n" ); document.write( "Part II 7.00% per annum ---y
\n" ); document.write( "Total investment
\n" ); document.write( "x + 1 y= 1700 -------------1
\n" ); document.write( "Interest on both investments
\n" ); document.write( "9.00% x + 7.00% y= 131
\n" ); document.write( "Multiply by 100
\n" ); document.write( "9 x + 7 y= 13100.00 --------2
\n" ); document.write( "Multiply (1) by -9
\n" ); document.write( "we get
\n" ); document.write( "-9 x -9 y= -15300.00
\n" ); document.write( "Add this to (2)
\n" ); document.write( "0 x -2 y= -2200
\n" ); document.write( "divide by -2
\n" ); document.write( " y = 1100 - x)
\n" ); document.write( "Part I 9.00% $ 600
\n" ); document.write( "Part II 7.00% $ 1100
\n" ); document.write( "
\n" ); document.write( "CHECK
\n" ); document.write( "600 --------- 9.00% ------- 54.00
\n" ); document.write( "1100 ------------- 7.00% ------- 77.00
\n" ); document.write( "Total -------------------- 131.00
\n" ); document.write( " \n" ); document.write( "
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