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7 votes
How many ounces of pure acid should be added to 300 ounces of 12% acid solution to produce a solution that is 25%?

User Enavuio
by
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1 Answer

23 votes
23 votes

Answer:

52 ounces

Explanation:

You want the number of ounces of pure acid to be added to 300 ounces of 12% acid solution to produce a solution that is 25%.

Setup

Let x represent the number of ounces of acid added. Then the amount of acid in the desired solution is ...

12%(300) +100%(x) = 25%(300 +x)

Solution steps

Subtracting (25%(x) +12%(300)) from both sides, we get ...

75%(x) = 13%(300)

Dividing by the coefficient of x, we find ...

x = (13)(300)/75 = 52

52 ounces of pure acid should be added to make a 25% acid solution.

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Additional comment

In the original solution, there are 12%(300) = 36 ounces of acid. In the 352 ounces of final solution, there will be 36+52 = 88 ounces of acid, a proportion of 88/352 = 1/4 = 25%.

User Ryan Knell
by
2.9k points