document.write( "Question 990669: How much water must be evaporated from 30 gallons of a 7% salt solution to make a 12% salt solution? \n" ); document.write( "

Algebra.Com's Answer #610666 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+x+\"$ = gallons of water to be evaporated
\n" ); document.write( "You start with $\"+.07%2A30+=+2.1+\"$ gallons of salt
\n" ); document.write( "and you end up with the same amount
\n" ); document.write( "---------------------
\n" ); document.write( " $\"+2.1+%2F+%28+30+-+x+%29+=+.12+\"$
\n" ); document.write( " $\"+2.1+=+.12%2A%28+30+-+x+%29+\"$
\n" ); document.write( " $\"+2.1+=+3.6+-+.12x+\"$
\n" ); document.write( " $\"+.12x+=+3.6+-+2.1+\"$
\n" ); document.write( " $\"+.12x+=+1.5+\"$
\n" ); document.write( " $\"+x+=+12.5+\"$
\n" ); document.write( "12.5 gallons should be evaporated
\n" ); document.write( "---------------
\n" ); document.write( "check:
\n" ); document.write( " $\"+2.1+%2F+%28+30+-+x+%29+=+.12+\"$
\n" ); document.write( " $\"+2.1+%2F+%28+30+-+12.5+%29+=+.12+\"$
\n" ); document.write( " $\"+2.1+%2F+17.5+=+.12+\"$
\n" ); document.write( " $\"+2.1+=+.12%2A17.5+\"$
\n" ); document.write( " $\"+2.1+=+2.1+\"$
\n" ); document.write( "OK \n" ); document.write( "

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