Question

Twenty - seven small cubes are glued together to make a big cube. The exterior of the big cube is painted yellow in colour. How many among each of the 27 small cubes would have painted yellow on
(i) only one of it's faces?
(ii) two of it's faces?
(iii) three of it's faces?

Answer 1

total number of small cube = 27
it means.... for making one big cube...9 small cubes is used for making one face
then, 3×3×3 =27
now, A/q,
1. each face have only one cube painted one side
  total number =6 cube
2. each face have 4 cube painted 2 sides and shared by two faces
total number = (6×4)/2 =12 cubes
3.each corner have 3 sides painted
total number = 8