document.write( "Question 892994: How many gallons of a 60% solution should Angela add to 30 gallons of a 10% solution to produce a 40% solution? \n" ); document.write( "

Algebra.Com's Answer #540982 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+x+\"$ = gallons of 60% solution needed
\n" ); document.write( " $\"+.6x+\"$ = gallons of concentrate in 60% solution
\n" ); document.write( " $\"+.1%2A30+=+3+\"$ = gallons of concentrate in 10% solution
\n" ); document.write( "-------------------------------------------------
\n" ); document.write( " $\"+%28+.6x+%2B+3+%29+%2F+%28+x+%2B+30+%29+=+.4+\"$
\n" ); document.write( " $\"+.6x+%2B+3+=+.4%2A%28+x+%2B+30+%29+\"$
\n" ); document.write( " $\"+.6x+%2B+3+=+.4x+%2B+12+\"$
\n" ); document.write( " $\"+.2x+=+9+\"$
\n" ); document.write( " $\"+x+=+45+\"$
\n" ); document.write( "45 gallons of 60% solution must be added
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+.6x+%2B+3+%29+%2F+%28+x+%2B+30+%29+=+.4+\"$
\n" ); document.write( " $\"+%28+.6%2A45+%2B+3+%29+%2F+%28+45+%2B+30+%29+=+.4+\"$
\n" ); document.write( " $\"+%28+27+%2B+3+%29+%2F+75+=+.4+\"$
\n" ); document.write( " $\"+30+=+.4%2A75+\"$
\n" ); document.write( " $\"+30+=+30+\"$
\n" ); document.write( "OK \n" ); document.write( "

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