document.write( "Question 620904: An investor invested a total of $1800 in two mutual funds. One fund earned a 6% profit value while the other earned 4% profit. If the investor's profit was $80, how much was in each mutual fund? The amount invested in the fund that earned 6% was __________. The amount invested in the fund that earned 4% was ________> \n" ); document.write( "
Algebra.Com's Answer #390445 by dragonwalker(73)\"\" \"About 
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let us say that the amount invested in the 6% fund is x. Therefore the amount invested in the 4% fund is 1800-x\r
\n" ); document.write( "\n" ); document.write( "Let us change the % to a value, so 4% can be written 4/100 = 0.04 and 6% can be written 0.06\r
\n" ); document.write( "\n" ); document.write( "Now we multiply the interest rate by the amount invested for each fund which added together equal $80:\r
\n" ); document.write( "\n" ); document.write( "0.06(x) + 0.04(1800-x) = 80\r
\n" ); document.write( "\n" ); document.write( "solve for x:
\n" ); document.write( "0.06x + 72 - 0.04x = 80
\n" ); document.write( "0.02x = 8\r
\n" ); document.write( "\n" ); document.write( "To find x divide both sides by 0.02:
\n" ); document.write( "0.02x/0.02 = 8/0.02\r
\n" ); document.write( "\n" ); document.write( "x = 400\r
\n" ); document.write( "\n" ); document.write( "So the amount invested at 6% rate was $400 and therefore the amount at 4% was $1400\r
\n" ); document.write( "\n" ); document.write( "To check we multiply the amount invested by the interest rate for each and added together we should get $80\r
\n" ); document.write( "\n" ); document.write( "0.06(400) + 0.04(1400) = 80 !!!\r
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