Quantitative Aptitude – Cubes – The six faces of a wooden cube of side
XAT 2021 Exam Paper – Quantitative Aptitude – Cubes – The six faces of a wooden cube of side
Q. The six faces of a wooden cube of side 6 cm are labelled A, B, C, D, E and F respectively. Three of these faces A, B, and C are each adjacent to the other two, and are painted red. The other three faces are not painted. Then, the wooden cube is neatly cut into 216 little cubes of equal size. How many of the little cubes have no sides painted?
135
91
100
108
125
Answer: 125
Solutions:
Since A, B and C are adjacent faces. If we remove them, the resultant solid will also be a cube with side 5 and with no face painted.
Thus number of unpainted little cubes = 5^3=125