Question

The perimeter of one face of a cube is 20 cm. Find (i) the total area of the 6 faces, (ii) the volume of the cube.

Answer 1

Given:

Perimeter of one face (square) = 20 cm.

Step-wise calculation:

1. Let edge (side) = a.

Perimeter of square face = 4a.

So, 4a = 20 

⇒ a = 20 ÷ 4

= 5 cm

2. Total area of 6 faces (total surface area) = 6a².

Using a = 5:

6 × 5² 

= 6 × 25

= 150 cm²

3. Volume of cube = a³. 

Using a = 5:

5³ = 125 cm³

1. Total area of the 6 faces = 150 cm².
2. Volume of the cube = 125 cm³.