The volume of a wall is given as 12.8 cubic meters. The height of the wall is 5 times its breadth, and the length is 8 times its height. Find the breadth of the wall.

Correct option is B

Given:
The height of the wall is 5 times its breadth.
The length of the wall is 8 times its height.
The volume of the wall is 12.8 cubic meters.
Formula Used:
Volume = Length × Height × Breadth
Solution:
Let the breadth of the wall be "b".
The height of the wall is 5b, and the length of the wall is 40b (since length = 8 times the height).
Volume = Length × Height × Breadth
12.8 = 40b × 5b × b

12.8 = 200 $$b^3$$​​
$$b^3$$​= $$\frac{12.8 }{ 200}$$​​
$$b^3$$​ = 0.064
b = ∛(0.064)
b = 0.4 m = $$0.4 \times 100 = 40 cm$$​​
Therefore, the breadth of the wall is 40 cm