document.write( "Question 556303: Sue invested 10,000, part at 3.8% annual intrest and the balance at 7% annual intrest. How much is invested at each rate if a 1 year intrest payment is 603.68 \n" ); document.write( "

Algebra.Com's Answer #362113 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+a+\"$ = amount invested @ 3.8%
\n" ); document.write( "Let $\"+b+\"$ = amount invested @7%
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+a+%2B+b+=+10000+\"$
\n" ); document.write( "(2) $\"+.038a+%2B+.07b+=+603.68+\"$
\n" ); document.write( "multiply both sides of (2) by $\"+1000+\"$
\n" ); document.write( "(2) $\"+38a+%2B+70b+=+603680+\"$
\n" ); document.write( "Multiply both sides of (1) by $\"+38+\"$
\n" ); document.write( "and subtract (1) from (2)
\n" ); document.write( "(2) $\"+38a+%2B+70b+=+603680+\"$
\n" ); document.write( "(1) $\"+-38a+-+38b+=+-380000+\"$
\n" ); document.write( " $\"+32b+=+223680+\"$
\n" ); document.write( " $\"+b+=+6990+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"+a+%2B+b+=+10000+\"$
\n" ); document.write( "(1) $\"+a+%2B+6990+=+10000+\"$
\n" ); document.write( "(1) $\"+a+=+10000+-+6990+\"$
\n" ); document.write( "(1) $\"+a+=+3010+\"$
\n" ); document.write( "$3,010 = amount invested @ 3.8%
\n" ); document.write( "$6,990 = amount invested @7%
\n" ); document.write( "check answers:
\n" ); document.write( "(2) $\"+.038%2A3010+%2B+.07%2A6990+=+603.68+\"$
\n" ); document.write( "(2) $\"+114.38+%2B+489.3+=+603.68+\"$
\n" ); document.write( "(2) $\"+603.68+=+603.68+\"$
\n" ); document.write( "OK \n" ); document.write( "

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