document.write( "Question 476003: Lisa invested $8000, part at 4% and the rest at 5% per year. How much did she invest at each rate if her total return per year on the investments was $380? \n" ); document.write( "

Algebra.Com's Answer #326432 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"a\"$ = amount invested @ 4% per yr
\n" ); document.write( "Let $\"b\"$ = amount invested @ 5% per yr
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+a+%2B+b+=+8000+\"$
\n" ); document.write( "(2) $\"+.04a+%2B+.05b+=+380+\"$
\n" ); document.write( "----------------------
\n" ); document.write( "(2) $\"+4a+%2B+5b+=+38000+\"$
\n" ); document.write( "Multiply both sides of (1) by $\"4\"$ and subtract from (2)
\n" ); document.write( "(2) $\"+4a+%2B+5b+=+38000+\"$
\n" ); document.write( "(1) $\"+-4a+-+4b+=+32000+\"$
\n" ); document.write( " $\"+b+=+6000+\"$
\n" ); document.write( "and
\n" ); document.write( "(1) $\"+a+%2B+b+=+8000+\"$
\n" ); document.write( "(1) $\"+a+%2B+6000+=+8000+\"$
\n" ); document.write( "(1) $\"+a+=+2000+\"$
\n" ); document.write( "$2,000 is invested @ 4% per yr
\n" ); document.write( "$6,000 is invested @ 5% per yr \n" ); document.write( "

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