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5 votes
Twenty pounds of a salt-water solution contains fifteen percent salt. How much water must be added to weaken the solution to twelve percent salt?

3 lb
5 lb
12 lb

1 Answer

2 votes
(.15(20))/(20+w)=.12

3/(20+w)=.12

20+w=25

w=5

So 5 pounds of water must be added to the solution.


User Brandon Montgomery
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