Question

slant hieght is 21 M and dia-
meter of its base is 24 M find
curved surface area of cone.​

Answer 1

Given

• Slant height (l)= 21m
• Diameter= 24cm or
• radius = 24/2= 12cm

To Find :-

• CSA of cone

Solution :-

Using formula

$\sf\ \ C.S.A\ of\ cone = \pi r \ell\\ \\ \\ \implies\sf\ CSA= \dfrac{22}{\cancel{7}}\times 12\times \cancel{21}\\ \\ \\ \implies\sf\ CSA= 22\times 12\times 3\\ \\ \\ \implies\sf\ CSA= 66\times 12\\ \\ \\ \implies\sf\ \red{ CSA= 792m^2}$

Answer 2

Answer:

Given :-

• Slanght height of cone = 21 m
• Diameter = 24 m

To Find :-

CSA

Solution :-

Firstly we will half the diameter to find radius

Radius = 24/2

Radius = 12 cm

• CSA of cone = πrl

CSA = 22/7 × 12 × 21

[Cancelling 21 from 7]

CSA = 22 × 12 × 3

CSA = 66 × 12

CSA = 792 m³

Focus Zone :-

Volume of Cone = πr²h

TSA of cone = πrl + πr²