Set up X single rooms and Y double rooms, with a total monthly income of Z. According to the topic:

x+2y≥50

10x+ 15y≤480

x≥y

x & gt0，y & gt0

x，y∈Z

z=250x+300y

y=z/300 - 5/6x

Draw a picture, draw a parallel line with y=-5/6x. It is found that the optimal solution is the intersection of x+2y=50 and 10x+ 15y=480.

X=42，y=4。

At this time, z (max) = 250 * 42+300 * 4 =11700.