document.write( "Question 520137: Bernadette inherited $15,000 and invested it in two municipal bonds, which pay 7 percent and 9 percent simple interest. the annual interest is $1230. Find the amount at each rate. \n" ); document.write( "

Algebra.Com's Answer #345934 by Maths68(1474) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "Let\r
\n" ); document.write( "\n" ); document.write( "Amount invested at 7% = x
\n" ); document.write( "Amount invested at 9% = 15000-x\r
\n" ); document.write( "\n" ); document.write( "Given
\n" ); document.write( "Total interest on both investments = 1230\r
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\n" ); document.write( "\n" ); document.write( "7% * (x) + 9% * (15000-x) = 1230
\n" ); document.write( "7/100 * x + 9/100 * (15000-x) = 1230
\n" ); document.write( "Multiply by 100 both sides
\n" ); document.write( "7*x + 9 * (15000-x) = 1230 * 100
\n" ); document.write( "7x+ 135000-9x = 123000
\n" ); document.write( "7x-9x = 123000-135000
\n" ); document.write( "-2x=-12000
\n" ); document.write( "-2x/-2=-12000/-2
\n" ); document.write( "x=6000\r
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\n" ); document.write( "\n" ); document.write( "Amount invested at 7% = x = 6000
\n" ); document.write( "Amount invested at 9% = 15000-x = 15000 - 6000 = 9000\r
\n" ); document.write( "\n" ); document.write( "Check
\n" ); document.write( "=====
\n" ); document.write( "6000 * 7/100 + 9000 * 9/100 = 1230
\n" ); document.write( "60*7 + 90*9 = 1230
\n" ); document.write( "420 + 810 = 1230
\n" ); document.write( "1230=1230\r
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