document.write( "Question 164192: Please help me with this problem. I do not know how to set it up.\r
\n" ); document.write( "\n" ); document.write( "How can $5,400 be invested, part of it at 8% and the rest of it invested at 10%, so that the two investments will produce the same amount of interest? \n" ); document.write( "

Algebra.Com's Answer #120981 by aka042(26) $\"\"$ $\"About$

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Let's call the part of money invested at 8% x. Therefore, that amount of money will earn x*.08 interest. The rest of the money will be invested at 10%. The rest of the money is (5400-x), because it is whatever part of the 5400 was not invested at 8% (x). Therefore, that money will earn .1(5400-x) interest. Now we just need to equate these two expressions:
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\n" ); document.write( " $\".08x+=+.1%285400-x%29\"$ which we can expand to $\".08x+=+540+-+.1x\"$ . Let's combine like terms to arrive at $\".08x+%2B+.1x+=+.18x+=+540\"$ . Finally, divide both sides to arrive at $\"x+=+540%2F.18+=+3000\"$ . This means 3000 is invested at 8% interest and 5400-3000= 2400 is invested at 10% interest.
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\n" ); document.write( "To check our answer, we see that 3000 * .08 = 240 and 2400*.1 = 240 \n" ); document.write( "

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