11. (15 points) As shown in the figure, it is a water purification device, with the water flow direction from $A$ to $B$, and then to $C$. Originally, there were 10 pipes with the same flow rate between container $A$ and $B$, and 10 pipes with the same flow rate between $B$ and $C$. After swapping one pipe between $A$-$B$ and $B$-$C$, the flow rate increased by 30 cubic meters per hour. Question: By adjusting the pipeline layout, what is the maximum increase in flow rate from $A$ to $C$ in cubic meters?
11. (15 points) As shown in the figure, it is a water purification device, with water flowing from $A$ to $B$, and then to $C$. Originally, there were 10 pipes with the same flow rate between container $A$ and $B$, and 10 pipes with the same flow rate between $B$ and $C$. After swapping one pipe between $A$ and $B$ and one pipe between $B$ and $C$, the flow rate increased by 30 cubic meters per hour. Question: By adjusting the pipeline layout, what is the maximum increase in flow rate from $A$ to $C$ in cubic meters?
【Analysis】Since the flow rate increased by 30 cubic meters per hour after swapping one pipe between $A-B$ and $B-C$, it can be inferred that the pipes between $A-B$ and $B-C$ are different. One set of pipes has a higher flow rate than the other, and swapping one pipe increases the flow rate by 30 cubic meters per hour. Since the set of pipes with the higher flow rate has 10 pipes, swapping 5 pipes should result in the maximum increase in flow rate. According to the formula: increase in flow rate = number of pipes swapped × increase in flow rate per pipe, the solution can be derived.
【Solution】$30 \times (10 \div 2)$,
$$
\begin{array}{l}
=30 \times 5, \\
=150 \text { (cubic meters), }
\end{array}
$$

Answer: By adjusting the pipeline layout, the maximum increase in flow rate from $A$ to $C$ is 150 cubic meters.