11. (5 points) As shown in the figure, three small balls with a radius of 1 decimeter each are placed into a cylindrical container that is already $\frac{1}{3}$ full of water. At this point, the water covers the balls, and the water level rises to $\frac{2}{5}$ of the container's height. The cylindrical container can hold a maximum of $\qquad$ cubic decimeters of water.
11. (5 points) As shown in the figure, three small balls with a radius of 1 decimeter each are placed into a cylindrical container that is $\frac{1}{3}$ full of water. At this point, the water covers the balls, and the water level rises to $\frac{2}{5}$ of the container's height. The cylindrical container can hold a maximum of 188.4 cubic decimeters of water.

【Solution】Solution: $\frac{4}{3} \times 3.14 \times 1^{3} \times 3 \div\left(\frac{2}{5}-\frac{1}{3}\right)$
$$
=12.56 \times 15
$$
$=188.4$ (cubic decimeters)
Answer: The cylindrical container can hold a maximum of 188.4 cubic decimeters of water.
Therefore, the answer is: 188.4.