Percentage 7469

The barrel contains 199 liters of 38% acid solution. What percentage of acid is created when we take 61 liters and replace it with the same amount of water?

Correct answer:

p =  26.3518 %

Step-by-step explanation:

$$\begin{gathered} V=199\text{l} \\ r=38\%=\frac{38}{100}=\frac{19}{50}=0.38 \\ k=V\cdot r=199\cdot 0.38=\frac{3781}{50}=75.62\text{l} \\ {k}_2=k-61\cdot r=75.62-61\cdot 0.38=\frac{1311}{25}=52.44\text{l} \\ p=100\cdot \frac{k_2}{V}=100\cdot \frac{52.44}{199}=26.3518\% \end{gathered}$$

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