Question

A roof of dimensions 6.5 m x 5.5 m is covered on all sides by a 1 m high wall of width 30 cm. The remaining part of the roof is covered with a waterproof covering at 19 per m2. Find the total cost of waterproofing​

Answer 1

$\sf{\underline{Given:}}$

Length $\sf{= 6.5\:m}$

Breadth $\sf{= 5.5\:m}$

Width of the wall $\sf{= 30\:cm}$

$\sf{\underline{New:}}$

$\implies$ Length $\sf{= 6.5 - 0.6 = 5.9\:m}$

$\implies$ Breadth $\sf{= 5.5 - 0.6 = 4.9\:m}$

$\sf{\underline{Note:}}$

Here 0.6 that is 60 cm is subtracted from both the length and the breadth.

$\sf{\underline{Now:}}$

The remaining part of the roof:

$\sf{ = 5.9 \times 4.9}$

$\sf{ = 28.91 \: {m}^{2}}$

$\sf{\underline{Therefore:}}$

Note: $\sf{Rs.19/m^{2}}$ (Given)

The cost of waterproofing this area

$\sf{= 28.91 \times 19}$

$\sf{= 549.29}$

$\sf{\underline{Therefore:}}$

The total cost of waterproofing is $\sf{Rs.\:549.29}$