document.write( "Question 719910: Please help. Thankyou. \r
\n" ); document.write( "\n" ); document.write( "An aquarium owner tested the chemical levels of the water in her 50 gallon tank. The water tested with a level of 2% of a certain chemical. She wanted to drop the level to a safe level of 1.25% How much of the aquarium water should be removed and pure water added to the aquarium? \n" ); document.write( "

Algebra.Com's Answer #441585 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+x+\"$ = gallons of water to be removed and
\n" ); document.write( "replaced with pure water
\n" ); document.write( "The owner starts out with $\"+.02%2A50+=+1+\"$ gallon of the chemical
\n" ); document.write( "The gallons of chemical that are removed when the water is drained
\n" ); document.write( "is $\"+.02x+\"$
\n" ); document.write( "Note that there are 50 gallons at the start and 50 gallons at the end
\n" ); document.write( "----------------
\n" ); document.write( " $\"+%28+1+-+.02x+%29+%2F+50+=+.0125+\"$
\n" ); document.write( " $\"+1+-+.02x+=+.0125%2A50+\"$
\n" ); document.write( " $\"+1+-+.02x+=+.625+\"$
\n" ); document.write( " $\"+.02x+=+1+-+.625+\"$
\n" ); document.write( " $\"+.02x+=+.375+\"$
\n" ); document.write( " $\"+x+=+18.75+\"$
\n" ); document.write( "18.75 gallons should be drained and replaced with pure water
\n" ); document.write( "check:
\n" ); document.write( " $\"+%28+1+-+.02%2A18.75+%29+%2F+50+=+.0125+\"$
\n" ); document.write( " $\"+%28+1+-+.375+%29+%2F+50+=+.0125+\"$
\n" ); document.write( " $\"+.625+%2F+50+=+.0125+\"$
\n" ); document.write( " $\"+.625+=+.625+\"$
\n" ); document.write( "OK\r
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