document.write( "Question 679432: Hi!
\n" ); document.write( "Barbara has a bucket that holds 18 fl oz. She mixes 14.4 fl oz of water and 3.6 oz of ammonia to make a cleaning solution. She then decides to replace a portion of the cleaning solution to create a cleaning solution with 25% ammonia. How much cleaning solution should be replaced by ammonia?\r
\n" ); document.write( "\n" ); document.write( "So far I have figured out that 14.4 fl oz is 80% of 18 fl oz and 3.6 fl oz is 20 % of 18 fl oz. Are the percentages part of the concentration? If not, what are they?
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Algebra.Com's Answer #421975 by KMST(5328)\"\" \"About 
You can put this solution on YOUR website!
The solution she has in the bucket has 80% water (as you found out), including 14.4 fl oz. water in a total of 18 fl oz. solution.
\n" ); document.write( "Barbara will need to add ammonia, but only after removing some (\"x\" fl oz.) of the solution she has in the bucket.
\n" ); document.write( "If Barbara wants an 18 fl oz. bucket full of 25% ammonia, she will need to have in that bucket
\n" ); document.write( "\"18%2A0.25=4.5\" fl oz. ammonia (25% ammonia) and
\n" ); document.write( "\"18%2A0.75=13.5\" fl oz. water (75% water).
\n" ); document.write( "Barbara will have to start by removing some of that 80% water solution to end up with just 13.5 fl oz. water in the bucket.
\n" ); document.write( "Removing \"x\" fl oz. of solution, gets rid of \"0.8x\" fl oz. of water,
\n" ); document.write( "leaving \"14.4-0.8x\" fl oz. of water.
\n" ); document.write( "Since the amount of water needed is \"13.5\" fl oz., our equation is
\n" ); document.write( "\"highlight%2813.5=14.4-0.8x%29\"
\n" ); document.write( "\"13.5=14.4-0.8x\" --> \"0.8x=14.4-13.5\" --> \"0.8x=0.9\" --> \"x=0.9%2F0.8\" --> \"highlight%28x=1.125%29\" fl oz.\r
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