You just have to split the figures in different parts...
- First Picture:
- the total length is 130, so the upper and bottom rectangles have 50ft. as showed, and the middle one is 130-(50x2) = 30
- The second step is get the 2 holes área to subtract from the “total rectangle without holes area” (30x40=1200)x2 and then (20,150-1400=18,750) so, the total area from the rectangle with the holes is 18,750!
