Q. A cube of sides 9 is first painted red and then cut into smaller cubes of side 3. How many of the smaller cube have painted on exactly 2 sides?
Option
A) 30
B) 24
C) 12
D) 8

• n=side of big cube/side of small cube
  and no. Of smaller cubes with two surfaces painted is (n-2)*12
  (3-2)*12=12 ans
• 11 years agoHelpfull: Yes(7) No(2)
• the question is,cube with 9units(9cm,9m..etc)painted with red,when divided into smaller cubes of 3units,what number of cubes has its two faces painted?
  
  so answer is,only edged cubes will have 2 faces painted.That counts to 8 cubes,1 each in the edge of large cube.
• 11 years agoHelpfull: Yes(3) No(2)
• @NANDISH...sorry bro, read the question carefully. It asked to find out the no of smaller cubes which hav painted on xactly 2 sides.
  
  Answer is 12.
  Bcoz, corner part hav painted 3 sides.
  Only middle part is painted xactly 2 side.
  
  Means, six sides and 2 cubes we will get for each side.
  
  So, answer is 12.
• 10 years agoHelpfull: Yes(3) No(1)
• ans:24
  (n-2)12
  (3-2)12=12
• 11 years agoHelpfull: Yes(2) No(6)
• Shalu ji can u explain this solution plz..
• 11 years agoHelpfull: Yes(2) No(1)