Question

The slant height and base diameter of a conical tomb are 25 m and 14 m respectively. Find the cost of white-washing its curved surface at the rate of 210 per 100 m².

Answer 1

Answer:

The cost of white washing is Rs.1155

Step-by-step explanation:

Given:

$\text{Slant height, l}=25\:cm$

$\text{Diameter}=14cm$

$\implies\text{Radius, r}=7\:cm$

$\text{Curved surface area of conical tomb }=\pi\:r\:l$

$=\frac{22}{7}\times\:7\times25$

$=22\times25$

$=550\:m^2$

$\text{The cost of white washing per }1\:m^2\:is\:Rs.2.10$

$\text{The cost of white washing for }550\:m^2=550\times\:2.10$

$\implies\text{The cost of white washing for }550\:m^2=Rs.1155$

Answer 2

Answer:

Cost of white washing the curved surface area of the cone is 1155 Rs.

Step-by-step explanation:

In the question,

The slant height of the conical tomb, l = 25 m

The base diameter of the tomb is, d = 14 m

So,

Radius of the tomb is, r = d/2 = 7 m

Now,

We know that the Curved surface area of the cone is given by,

$C=\pi rl$

So,

$C=\frac{22}{7}\times 7\times 25\\C=550\ m^{2}$

Also,

The cost of white washing the curved surface area is $210 \ Rs.\ per\ 100\ m^{2}$.

So,

Cost of white washing will be,

$Cost=\frac{210}{100}\times 550\\Cost= 1155\ Rs.$

Therefore, the cost of white washing the curved surface area of the cone is 1155 Rs.