document.write( "Question 536491: Susan wants to mix 10 pounds of Virginia peanuts that cost $3.50 a pound with Spanish peanuts that cost $3.00 a pound to obtain a mixture that costs $3.40 a pound. How many pounds of Spanish peanuts should she use? \n" ); document.write( "

Algebra.Com's Answer #352394 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+x+\"$ = pounds of Spanish peanuts she needs
\n" ); document.write( "given:
\n" ); document.write( " $\"+3.5%2A10+=+35+\"$ cost of Virginia peanuts used
\n" ); document.write( " $\"+3x+\"$ = cost of Spanish peanuts used
\n" ); document.write( "-------------
\n" ); document.write( "( cost of peanuts ) / ( weight in pounds ) = cost per pound of mixture
\n" ); document.write( " $\"+%28+35+%2B+3x+%29+%2F+%28+10+%2B+x+%29+=+3.4+\"$
\n" ); document.write( " $\"+35+%2B+3x+=+3.4%2A%28+10+%2B+x+%29+\"$
\n" ); document.write( " $\"+35+%2B+3x+=+34+%2B+3.4x+\"$
\n" ); document.write( " $\"+.4x+=+1+\"$
\n" ); document.write( " $\"+x+=+2.5+\"$
\n" ); document.write( "She needs 2.5 pounds of spanish peanuts
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+35+%2B+3%2A2.5+%29+%2F+%28+10+%2B+2.5+%29+=+3.4+\"$
\n" ); document.write( " $\"+%28+35+%2B+7.5+%29+%2F+12.5+=+3.4+\"$
\n" ); document.write( " $\"+42.5+%2F+12.5+=+3.4+\"$
\n" ); document.write( " $\"+42.5+=+3.4%2A12.5+\"$
\n" ); document.write( " $\"+42.5+=+42.5+\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );