A solid block is formed by arranging some cubes of equal dimensions, as shown in the given figure. The block is painted on all of its surfaces except the base. How many cubes have none of the faces coloured?
A 0
B 12
C 8
D 6
how
Ans 1:
Class : Class 6
i think its b cause if you see it has a little bit of bold line on that part and if you count it it is 12 . i have not taken imo because i am an ieo student but in my opinion it is b.
Ans 4:
Class : Class 9
It is BConsider the front face as the base, OK? Then see that the 4 cubes in exact center of the base are not coloured on any faces.Like that there are 2 more such layers behind the center of the base right? so 4 x 3 = 12. Therefore 12 is answer. In the 4th layer the top face will be coloured right? We have been asked for no. of cubes with NO FACE COLOURED. So 12, 4 on base and 8 in the center of the cube!