Question

Question No: 7
27 small cubic blocks of side 1 m are joined to form a bigger cube. Now, if one block is removed from each corner of the bigger cube,
what will be the surface area (in m?) of the resultant object?
27
30
46
54​

Answer 1

If we have a cube with 1*1*1 dimensions, how many more similar cubes do we have to put around it to get the shape of a perfect cube? 64 small cubes joined to form a single large cube. The outer surface of the cube is painted by red color.

hope it helps you ....

Answer 2

The surface area of the resultant object will be 54 m²

Given:

27 small cubic blocks make a cube.

side of small cubes = 1 m²

One block is removed from each corner of the bigger cube

Find:

The surface area of the resultant object

Solution:

• We know 3×3×3 = 27
• So the larger cube will have 3 small cubes on each edge.
• So the length of each side of the cube = a =3 m
• The surface area of a cube = 6a²
•                                              = 6 ×3×3
•                                               = 54m²
• If we remove a cube from one corner, we will be able to see three faces of 3 adjacent smaller cubes.
• This will contribute 3a² = 3 m² surface area.
• Each of the removed cubes at the corner contributed a 3a² = 3m² surface area.
• So the net effect is balanced.
• Removing cubes from the corner doesn't change the surface area of the resultant object, both will have the same surface area.
• The surface area of both the shapes will be 54 m²
• #SPJ6