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Cuboids, Rectangular Prisms and Cubes
A cuboid is a boxshaped object. It has six flat sides and all angles are right angles.
And all of its faces are rectangles.
It is also a prism because it has the same crosssection along a length. In fact it is a rectangular prism.



If at least two of the lengths are equal then it can also be called a square prism.
(Note that this doesn't stop it from also being called a rectangular prism if you want!)

So a cube is just a special case of a square prism, and
a square prism is just a special case of a rectangular prism.
And they are all cuboids.

Note: The name "cuboid" comes from "cube" and oid (which means "similar to, or resembling") and so indicates "it is like a cube".
Another use of oid is when we talk about the Earth being a spheroid (not exactly a sphere, but close).

Volume and Surface Area
The volume of a cuboid is simply: 
Volume = width × depth × height 
Which can be written as: 
V = wdh 


And the surface area is: 
A = 2wd + 2dh + 2hw

Example Calculation

Find the volume and surface area of this cuboid.
V = 4×5×10 = 200
A = 2×4×5 + 2×5×10 + 2×10×4
= 40+100+80 = 220

Examples of Cuboids
Cuboids are very common in our world, from boxes to buildings we see them everywhere. You can even fit them inside other cuboids!




A box with a slot cut as a handle 
Cuboids in a cuboid room 
Boxes for model trains 
Now that's just silly! 


