Medium
A cube of side 3 centimeters is painted and divided into smaller cubes of side 1 centimeter. Number of cubes with 2 faces painted is:
Explanation
Explanation
Cubes with exactly two faces painted are the edge cubes (excluding corners). A cube has 12 edges, and each edge contributes exactly one such cube (the middle cube of that edge), giving 12 cubes.
PRO TIP
Re-check your working by substituting the answer back into the original question.