document.write( "Question 160290: We've tried and tried.........
\n" ); document.write( "Mary makes 3 investments. The investment that pays 12% is twice the amount of the account that pays 9%. The amount invested at 10% is $500 more than the amount invested at 9%. If the annual interest income is $1555, how much money is invested at each rate?
\n" ); document.write( "We tried making the box-
\n" ); document.write( " P R T = I
\n" ); document.write( "1. 2x .12 1
\n" ); document.write( "2. x .09 1
\n" ); document.write( "3. x+500 .10 1\r
\n" ); document.write( "\n" ); document.write( "We're stuck. Line #1 we got $840.00
\n" ); document.write( " #2 $315.00
\n" ); document.write( "Then it doesn't add up to 1555. Can you help us figure this out?
\n" ); document.write( "Thanks,
\n" ); document.write( "Tricia \n" ); document.write( "

Algebra.Com's Answer #118280 by checkley77(12844) $\"\"$ $\"About$

You can put this solution on YOUR website!
.12*2x+.09x+.10(x+500)1,555
\n" ); document.write( ".24x+.09x+.10x-50=1,555
\n" ); document.write( ".43x=1,555-50
\n" ); document.write( ".43x=1,505
\n" ); document.write( "x=1,505/.43
\n" ); document.write( "x=3,500 is the amount invested @ 9%
\n" ); document.write( "2*3,500=7,000 invested @ 12%
\n" ); document.write( "3,500+500=4,000 invested @10%
\n" ); document.write( "Proof:
\n" ); document.write( ".12*7,000+.09*3,500+.10*4,000=1,555
\n" ); document.write( "840+315+400=1,555
\n" ); document.write( "1,555=1,555 \n" ); document.write( "

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