Problema Solution

to clean a concrete driveway, a contractor needs a solution that is 30% acid. how many ounces of A 50% acid solution must be mixed with 15 ounces of a 21% solution to obtain a 30% acid solution

Answer provided by our tutors

Let 'x' represent the ounces of 50% acid.

0.50x + 0.21*15 = 0.30*(x + 15)

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click here to see the equation solved for x

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x = 6.74 oz

6.75 ounces of 50% acid should be used to obtain the 30% acid solution.