Question

$\huge \mathfrak{Question}$​

Answer 1

let width be = w

height = h = 5 × w = 5w

length = l = 8 × h = 8 × (5w) = 40w

volume of cuboid shape wall = lwh

12.8 = 40w × w × 5w

12.8 = 200w³

12.8 ÷ 200 = w³

0.064 = w³

64/1000 = w³

4/10 = w

0.4m = w = width

length = 40w = 40 × 4/10 = 4 × 4 = 16m

Its length is 16m.

Answer 2

Answer:

Lets assume that the breadth(b) of the wall is x

Since the height(h) of the wall is five times that of its breadth,

h = 5b or h = 5x

Now, the length(l) of the wall is eight times that of its height,

l = 8h or l = 8(5x) = 40x

Given that the volume(v) is 12.8 cubic meters

v = lbh ( volume of a cuboid having length,breadth and height)

12.8 = (x)(5x)(40x)

12.8 = 200 x³

x³ = 0.064 meter cube

x = 0.4 meter.

Therefore, the breadth of the wall is 0.4 since we assumed in the beginning that it was equal to x