document.write( "Question 726142: \r
\n" ); document.write( "\n" ); document.write( "A pharmacist needs 70 liters of a 50% alcohol solution. She has available a 30% solution and a 80% solution. How many liters of each solution should she mix to obtain what she needs?
\n" ); document.write( "

Algebra.Com's Answer #444500 by checkley79(3341)\"\" \"About 
You can put this solution on YOUR website!
.80X+.30(70-X)=.5*70
\n" ); document.write( ".80X+21-.30X=35
\n" ); document.write( ".50X=35-21
\n" ); document.write( ".50X=14
\n" ); document.write( "X=14/.5
\n" ); document.write( "X=28 L. OF 80% SOLUTION IS USED.
\n" ); document.write( "70-28=42 L. OF 20% SOLUTION IS USED.
\n" ); document.write( "PROOF:
\n" ); document.write( ".80*28+.30*42=.5*70
\n" ); document.write( "22.4+12.6=35
\n" ); document.write( "35=35
\n" ); document.write( "
\n" ); document.write( "
\n" );