If after 500 grams of water were added to the 24%-solution of alcohol, the strength of the solution decreased by one-third, how much of the 24%-solution was used?
Choices.
A) 180 grams  B) 220 grams  C) 250 grams  D) 350 grams  E) 1000 grams
I too think 1000 grams should be the answer.   My reasoning is   The h20 content in 200 gms of water is 1   h20 content in 24% solution is 0.76   Resulting new solution's concentration decreases by one third means. Now it becomes 16% solution which means h20 content is 0.84   Let amount of solution be X   Then the equation can be set up   500*1 + 0.76X = 0.84 (X+500)   0.08X = 80   8X = 8000   X = 1000 (ANS 1000 grams)
<result>E</result>
If after 500 grams of water were added to the 24%-solution of alcohol, the strength of the solution decreased by one-third, how much of the 24%-solution was used?