I have to assume that the 24, the 72, and the 18 are feet.
If those are the dimensions of a rectangular prism, like a box, a crate,
or a humongous block of ice, then
Volume = (length) x (width) x (height) =
(24-ft) x (72-ft) x (18-ft) = 31,104 cubic ft
If those numbers are inches, then here's the easy way to handle it:
24 inches = 2 ft
72 inches = 6 ft
18 inches = 1.5 ft
Volume = (length) x (width) x (height) =
(2ft) x (6ft) x (1.5ft) = 18 cubic feet
