Question

I need help i don’t quite understand

Answer 1

The volume of a rectangular paralellepiped, also known as a box, is length times width times height.

The big box is 20×7×12

The hallway is a box 3×5×12

Our volume is the difference,

V = 20×7×12 - 3×5×12 = 1500 cubic feet

Answer: 1500