Question

The volume of a wall, 5 times as high as it is broad and 8 times as long as it is high, is 12.8 m³. The breadth of the wall is ______.

Options

• 30 cm

•  40 cm

• 22.5 cm

• 25 cm

Answer 1

The volume of a wall, 5 times as high as it is broad and 8 times as long as it is high, is 12.8 m³. The breadth of the wall is 40 cm.

Explanation:

Let the breadth of the wall be x cm.

Then, its height = 5x cm

And its length = (8 × 5x) = 40 × cm

Hence, the volume of the wall = (40x × x × 5x) cm³

It is given that the volume of the wall = 128 m³.

Therefore,

⇒ 40x × x × 5x  = 128 × 100 × 100 × 100

⇒ 200x³ = 128000000

⇒ x³ = 640000

⇒ x³ = (40 × 40 × 40)

⇒ x = 40 cm