14.3. A 30% hydrochloric acid solution was mixed with a 10% solution, resulting in 600 g of a 15% solution. How many grams of each solution were taken?

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14.3. Let $x$ be the number of grams of the 30% solution. Then the 10% solution was taken in the amount of ( $600-x$ ) g. We have the equation: $0.3 x + 0.1(600-x) = 0.15 \cdot 600$. From this, $x=150$. Answer: 150 g of the 30% solution and 450 g of the 10% solution were taken.

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