document.write( "Question 1046721:
\n" ); document.write( "How much pure acid should be mixed with 2 gallons of a 60% acid solution in order to get a 90% acid solution? \n" ); document.write( "

Algebra.Com's Answer #662176 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+x+\"$ = gallons of pure acid needed
\n" ); document.write( " $\"+.6%2A2+=+1.2+\"$ = gallons of pure acid in 60% solution
\n" ); document.write( "---------------------
\n" ); document.write( " $\"+%28+x+%2B+1.2+%29+%2F+%28+x+%2B+2+%29+=+.9+\"$
\n" ); document.write( " $\"+x+%2B+1.2+=+.9%2A%28+x+%2B+2+%29+\"$
\n" ); document.write( " $\"+x+%2B+1.2+=+.9x+%2B+1.8+\"$
\n" ); document.write( " $\"+.1x+=+.6+\"$
\n" ); document.write( " $\"+x+=+6+\"$
\n" ); document.write( "-------------
\n" ); document.write( "6 gallons of pure acid are needed
\n" ); document.write( "-------------
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+x+%2B+1.2+%29+%2F+%28+x+%2B+2+%29+=+.9+\"$
\n" ); document.write( " $\"+%28+6+%2B+1.2+%29+%2F+%28+6+%2B+2+%29+=+.9+\"$
\n" ); document.write( " $\"+7.2+%2F+8+=+.9+\"$
\n" ); document.write( " $\"+7.2+=+.9%2A8+\"$
\n" ); document.write( " $\"+7.2+=+7.2+\"$
\n" ); document.write( "OK \n" ); document.write( "

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