In a mixture problem, it helps to separate out the "water" from the other element.

so with 40 liters, 60% means there are 24 liters of "salt" and 16 liters of water.

If you want to have 45% mixture when you're done, you'll have 18 liters of salt (45% of 40 = 18). So, you need to get rid of 6 liters of salt. If for every liter of mixture, you have 0.6 liters of salt, then you need to get rid of 10 liters of mixture and replace all 10 liters with water.

reply2spg wrote:

Forty liters of a 60% salt solution are reduced to a 45% solution. How much must be drained off and replaced with distilled water to that the resulting solutions will contain only 45% salt?

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J Allen Morris

**I'm pretty sure I'm right, but then again, I'm just a guy with his head up his a$$.

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