document.write( "Question 995979: How much pure acid should be mixed with 55 gallons of aa 40 %40% acid solution in order to get 50% acid​ solution? \n" ); document.write( "
Algebra.Com's Answer #614587 by josmiceli(19441)\"\" \"About 
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Let \"+x+\" = gallons of pure acid to be added
\n" ); document.write( "\"+.4%2A55+=+22+\" gallons of pure acid in 40% solution
\n" ); document.write( "------------------
\n" ); document.write( "\"+%28+x+%2B+22+%29+%2F+%28+x+%2B+55+%29+=+.5+\"
\n" ); document.write( "\"+x+%2B+22+=+.5%2A%28+x+%2B+55+%29+\"
\n" ); document.write( "\"+x+%2B+22+=+.5x+%2B+27.5+\"
\n" ); document.write( "\"+.5x+=+5.5+\"
\n" ); document.write( "\"+x+=+11+\"
\n" ); document.write( "11 gallons of pure acid needs to be added
\n" ); document.write( "---------------
\n" ); document.write( "check:
\n" ); document.write( "\"+%28+x+%2B+22+%29+%2F+%28+x+%2B+55+%29+=+.5+\"
\n" ); document.write( "\"+%28+11+%2B+22+%29+%2F+%28+11+%2B+55+%29+=+.5+\"
\n" ); document.write( "\"+33%2F66+=+.5+\"
\n" ); document.write( "\"+.5+=+.5+\"
\n" ); document.write( "OK
\n" ); document.write( "
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