document.write( "Question 961475: Forty liters of a 60% salt solution are diluted to produce a 45% solution. How much must be drained and replaced with distilled water so that the resulting solution will contain only 45% salt? \n" ); document.write( "

Algebra.Com's Answer #587509 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"+x+\"$ = liters of 60% solution to be
\n" ); document.write( "drain off and replaced with water
\n" ); document.write( "------------------------------------
\n" ); document.write( " $\"+.6x+\"$ = liters of salt in the 60% solution
\n" ); document.write( "that is drained off
\n" ); document.write( "--------------------------------------
\n" ); document.write( " $\"+.6%2A40+=+24+\"$ liters of salt to begin with
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\n" ); document.write( " $\"+%28+24+-+.6x+%29+%2F+40+=+.45+\"$
\n" ); document.write( " $\"+24+-+.6x+=+.45%2A40+\"$
\n" ); document.write( " $\"+24+-+.6x+=+18+\"$
\n" ); document.write( " $\"+.6x+=+24+-+18+\"$
\n" ); document.write( " $\"+.6x+=+6+\"$
\n" ); document.write( " $\"+x+=+10+\"$
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\n" ); document.write( "10 liters of solution should be drained off
\n" ); document.write( "and replaced with water
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\n" ); document.write( "check answer:
\n" ); document.write( "The total water you end up with is:
\n" ); document.write( " $\"+.4%2A%28+40+-+x+%29+=+.4%2A%28+40+-+10+%29+\"$
\n" ); document.write( " $\"+.4%2A30+=+12+\"$ liters
\n" ); document.write( "plus the $\"+10+\"$ I added = $\"+22+\"$ liters of water
\n" ); document.write( "I've still got $\"+40+\"$ liters total, so my concentration is:
\n" ); document.write( " $\"+%28+40+-+22+%29+%2F+40+\"$
\n" ); document.write( " $\"+18%2F40+=+.45+\"$
\n" ); document.write( "OK \n" ); document.write( "

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