Question

The circumference of the base of a cone is 44cm and the slant height is 25cm find the curved surface area of the cone

Answer 1

2pie r=44
r=7
curved surface area of cone=pie rl
=22/7×7×25=550cm^2

Answer 2

Answer:

Given that :-

The circumference of the base of a cone is 44cm and the slant height is 25cm

To find :-

the curved surface area of the cone

Circumference of the base = 2πr = 44 cm²

Slant Height ( l ) = 25 cm

We know that,

Slant Height = √ ( r² + h² )

Using the given information we can find out the radius of the cone.

⇒ 2πr = 44

⇒ r = 44 / 2π

⇒ r = 44 × 7/44

⇒ r = 7

Substituting in the Slant Height formula we get,

⇒ 25 = √ ( 7 )² + h²

Squaring on both sides we get,

⇒ 25² = 7²  + h²

⇒ 625 = 49 + h²

⇒ 625 - 49 = h²

⇒ 576 = h²

⇒ h = √576 = 24

Curved Surface Area of Cone = πrl

⇒ Curved Surface Area of Cone = 22/7 × 7 × 25

⇒ Curved Surface Area of Cone = 550 cm²