Determine the area of the yellow sector

Imade a fort for my pet gorilla by connecting two boxes. the first box is 555 meters long, 999 meters wide, and 999 meters high. the second box is 333 meters long, 888 meters wide, and 222 meters high.how many cubic meters of space does my gorilla have to play in her fort?

Answer question above and explain each step : )

What 8/12+8/11 in another way than and improper fraction