Question

A cube is coloured orange on one face, pink on the opposite face, brown on one face and silver on a face adjacent to the brown face. The other two faces are left uncoloured. It is then cut into 125 smaller cubes of equal:

How many cubes have at least two faces coloured ?

• A. 19
• B. 20
• C. 21
• D. 23

Answer 1

Answer: (C)

21

Cubes having at least two faces colored $=5+4+4+4+4=21$
Count the edges of the cube .
The first edge have five cubes and the remaining colored edge have 4.