Question

How much metal is needed to cast a cubical metal box with outer side 10 inches long if the thickness of its walls should be exactly 2 inches?

Answer 1

It would take `784 cm^3` of solid iron to make the box.

Explanation:

Find the volume of the box if the box was solid:
`V = s^3 = (10)^3 =`1000`cm^3`
If the side of the cube is 10 inches, and the width of the walls is 2 inches, then the width of the cube of air inside of the box is `10-2(2)=10-4=6` inches
The volume of that box is `(6)^3=216 cm^3`
Thus, the amount of metal to cast the box is `1000-216=784 cm^3`