UPSC Prelims 2019 · CSAT (Paper 2) · Q10

General Mental Ability

Hard · Cube painting combinatorics

A cube is painted red on one pair of opposite faces, green on another pair of opposite faces, and blue on the remaining pair. It is then cut into 64 identical smaller cubes (by making 3 equally spaced cuts parallel to each face). How many of the smaller cubes have exactly one face painted?