### Discussion :: Cube and Cuboid - Cube and Cuboid 3 (Q.No.2)

- Cube and Cuboid - Introduction
- Cube and Cuboid - Cube and Cuboid 1
- Cube and Cuboid - Cube and Cuboid 2
- «« Cube and Cuboid - Cube and Cuboid 3
- Cube and Cuboid - Cube and Cuboid 4
- Cube and Cuboid - Cube and Cuboid 5
- Cube and Cuboid - Cube and Cuboid 6
- Cube and Cuboid - Cube and Cuboid 7
- Cube and Cuboid - Cube and Cuboid 8
- Cube and Cuboid - Cube and Cuboid 9

The following questions are based on the information given below:

- A cuboid shaped wooden block has 4 cm length, 3 cm breadth and 5 cm height.
- Two sides measuring 5 cm x 4 cm are coloured in red.
- Two faces measuring 4 cm x 3 cm are coloured in blue.
- Two faces measuring 5 cm x 3 cm are coloured in green.
- Now the block is divided into small cubes of side 1 cm each.

Santhosh said: (Jan 1, 2012) | |

But according to l*2 + b*2 + h*2 =24??? |

Lalit Ku Sahu said: (May 27, 2014) | |

For cube: One face coloured= 6*(n-2)^2. = 6*(n-2)*(n-2). Similarly for CUBOID (4*3*5): One face coloured = 2*(L-2)*(B-2)+2*(B-2)*(H-2)+2*(H-2)*(L-2). =2*(4-2)*(3-2)+2*(3-2)*(5-2)+2*(5-2)*(4-2). = 2*2*1 + 2*1*3 + 2*3*2. = 4 + 6 + 12. = 22 ANSWER. |

Mohit said: (Aug 1, 2020) | |

@Lalit. Why you subtracting 2? |

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