A hollow cube of size 5 cm is taken,with a thichness of 1 cm.It is made of smaller cube of size 1 cm.if 4 faces of the outer surface of the cube are painted,total how many faces of the smaller cube remain unpainted?

• The big cube is completely hollow.. But, the thickness of
  its side is 1cm & this is made up of smaller cubes.
  
  Just like the walls of a room. The room is hollow, but, its
  thickness is due to smaller bricks. The 4 walls of this room
  is painted from the outside. And, you are asked totally how
  many sides of all the bricks are now unpainted.
  
  First, you need to know how many bricks (small cubes) are there.
  
  Size of big cube = 5cm
  Total volume of the big cube = 5*5*5 = 125cm^3
  
  Size of the hollow cube inside the big cube = 3cm
  Volume of the hollow space inside the big cube = 3*3*3 = 27cm^3
  
  Therefore, volume occupied by small cubes (or volume of
  thickness) = 125 - 27 = 98cm^3
  
  Size of each small cube = 1cm
  Volume of each small cube = 1*1*1 = 1cm^3
  Total number of small cubes in wall = 98 / 1 = 98
  
  In short, 98 small cubes make up the wall of the big cube.
  Each cube has 6 faces, so 98 cubes have = 98*6 faces = 588
  
  The four sides of the big cube have 100 painted faces.
  Because each big side has 25 faces of the small cubes.
  
  Therefore, total unpainted faces = 588 - 100 = 488
• 12 years agoHelpfull: Yes(13) No(0)
• The answer is 488.
  
• 12 years agoHelpfull: Yes(4) No(1)
• bigger cube is hollow
  so smaller cube will be made up of only surface material of bigger cube
  4 faces of bigger cube got painted before
  2 faces left
  material from dese two faces will get us number f unpainted faces
  area of one face= 5*5= 25
  dere r 2 faces
  so answer is 50
• 12 years agoHelpfull: Yes(2) No(5)
• 50. Each surface has 25 small surfaces. Thus 25 x 2=50.
• 12 years agoHelpfull: Yes(1) No(2)
• 50 or 10 ,each surface has either 10 or 50 small cube
• 12 years agoHelpfull: Yes(1) No(2)
• answer is 2
• 12 years agoHelpfull: Yes(0) No(6)