Explanation:

- Initially, the ratio of Solution “A” to Solution “B” is given as 3:2.

- Let the total quantity of the mixture be \( x \) L.

- Therefore, the amount of Solution “A” is \(\frac{3x}{5}\), and Solution “B” is \(\frac{2x}{5}\).

- When 10 L is removed, 6 L of Solution “A” and 4 L of Solution “B” are removed.

- Replacing this 10 L with Solution “B” only, we now have:

- Solution “A” = \(\frac{3x}{5} - 6\)

- Solution “B” = \(\frac{2x}{5} - 4 + 10\)

- The new ratio of Solution “A” to “B” is now 2:3.

- Solving the equation \(\frac{\frac{3x}{5} - 6}{\frac{2x}{5} + 6} = \frac{2}{3}\) gives \( x = 30 \).

- Thus, the total quantity of the mixture is 30 L.

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