Question

The slant height and base diameter of a conical tomb are 24 m and 14 m respectively. Find the cost of white-washing its curved surface at the rate of Rs 210 per 100 m 2 .​

Answer 1

Given:

• Slant height of the conical tomb : 24 m.
• Base diameter of the conical tomb : 14 m.
• The cost of white-washing the tomb at the rate of Rs 210 per 100 m².

To Find:

• The cost of white-washing the tomb =?

Step-by-step explanation :

Curved surface area of tomb = πrl

Given, Slant height, l = 24 m

Diameter = 14 m.

Now, As we know that,

Radius = Diameter /2

Substituting the values in the above formula, we get,

= 14/2 = 7 m.

Therefore, the radius = 7 m.

As We know that,

Curved Surface area of tomb = πrl

Substituting the values in the above formula, we get,

= 22/7 × 7 × 24

= 22 × 1 × 24

= 528.

Therefore, Curved Surface area of tomb = 528 m².

Now,

Cost of white-washing 100 m² area = Rs. 210

Cost of white-washing 1 m² area = Rs. 1/100×210

Cost of white-washing 528 m² area,

= 1/100 × 210 × 528

= 1,108.8.

Therefore, the cost of white-washing the tomb = Rs. 1,108.8

Answer 2

Question:

The slant height and base diameter of a conical tomb are 24 m and 14 m respectively. Find the cost of white-washing its curved surface at the rate of Rs 210 per 100 m².

Answer:

The cost of white-washing the tomb is Rs : 1108.8

Given:

➛Slant height of the conical tomb : 24 m.

➛Base diameter of the conical tomb : 14 m.

➛The cost of white-washing the tomb at

the rate of Rs 210 per 100 m².

To Find:

The cost of white-washing the tomb.

Solution:

We are given,

➛Slant height of the conical tomb : 24 m.

➛Base diameter of the conical tomb : 14 m.

➛The cost of white-washing the tomb at

the rate of Rs 210 per 100 m².

let r be the radius of the conical comb .

and l be slant height of the conical comb.

⛬ r = diameter / 2

➞ r = 14 / 2

➞ r = 7 m

and l = 24 m

we know,

The curved surface area of the comb : πrl

The curved surface area of the comb:

${\implies{\rm{\dfrac{22}{7} \times 7 \times 24}}}$

${\implies{\rm{\dfrac{22}{ \cancel{7}} \times \cancel{7} \times 24}}}$

${\implies{\rm{22 \times 24}}}$

${\implies{\pink{\boxed{\blue{\rm{The \ curved \ surface \ area \ of \ the \ comb = 528}}}}}}$

The cost of white- wasting 100m² area = Rs 210.

⛬The cost of white- wasting 1m² area = Rs 210/100.

⛬The cost of white- wasting 528m² area

= Rs ( 210/100)× 528

The cost of white- wasting 528m² area

= Rs 1108.8

${\implies{\pink{\boxed{\blue{\rm{The \ cost \ of \ white-wasting \ 528 \ {m}{2} \ area \ = Rs \ 1108.8}}}}}}$