Question

The curved surface area of a right circular cone of height 15cm and base diameter 16cm is:​

Answer 1

Given :-

• Height of cone (h) = 15cm
• Diameter of cone (d) = 16cm

To Find :-

• The Curved surface area of cone.

Solution :-

Diameter = Radius × 2

↪16 = Radius × 2

↪Radius = 16/2

↪Radius = 8cm

We know that,

l² = h² + r²

↪l = √h² + r²

↪l = √(15)² + (8)²

↪l = √225 + 64

↪l = √289

↪l = 17cm

As we know that,

Curved surface area of cone = πrl.

↪Curved surface area = 3.14 × 8 × 17

↪Curved surface area = 3.14 × 136

↪Curved surface area = 427.04cm²

Hence,

• The curved surface area of cone is 427.04cm².

Answer 2

Answer :

➥ The Curved surface area of cone = 427.04 cm²

Given :

➤ Height of cone (h) = 15 cm

➤ Diameter of cone (d) = 16 cm

To Find :

➤ Curved surface area of cone = ?

Required Solution :

To find Curved surface area of cone, at first we need to find the radius of right circular cone, after that we will find Slant height of right circular cone, after all this we will find Curved surface area of cone on the basis of conditions given above$.$

⇒ Radius = d/2

⇒ Radius = 16/2

⇒ Radius = 8 cm

Now, We find Slant height of cone.

As we know that

⇒ l = √h² + r²

⇒ l = √h² + r²

⇒ l = √(15)² + (8)²

⇒ l = √225 + 64

⇒ l = √289

⇒ l = 17 cm

Now, we have two elements used in formula, Radius and Slant height of a right circular cone,

• Radius of cone = 8 cm
• Slant height of cone = 17 cm

And we need to find Curved surface area of cone.

We can find Curved surface area of cone by using tue formula of Curved surface area of cone which says :

★ CSA of cone = πrl ★

Here,

• CSA is the Curved surface area of cone in cm².
• The value of π is 22/7 or 3.14.
• r is the Radius of cone in cm.
• l is the Slant height of cone in cm.

So let's find Curved surface area of cone (CSA) !

⇛ CSA of cone = πrl

⇛ CSA of cone = 22/7 × 8 × 17

⇛ CSA of cone = 3.14 × 8 × 17

⇛ CSA of cone = 25.12 × 17

⇛ CSA of cone = 427.04 cm²

║Hence, the Curved surface area of cone is 427.04 cm².║