Question

The slant height and height of a cone are in the ratio 4:3. The area of the
base is 154 cm. Find curved surface area of the cone.​

Answer 1

Answer:

C.S.A. ( Curved Surface Area) = 192.5 cm^2

Step-by-step explanation:

We have given the ratio of radius and height 4 : 3

Let Radius (r) be 4x

And Height (h) be 3x

Area of Base = πr^2

Given the area of base= 154

⇒πr^2 = 154

⇒22/7 × 16x^2 = 154

⇒x = 1.75

⇒ Radius (r) = 4x = 4 × (1.75)

= 7

Height(h) = 3x = 3 × (1.75)

= 5.25

Slant Height (l) = √r^2 + h^2

=√(4x^2) + (3x^2)

=√16x^2 + 9x^2

=√25x^2

= 5x

= 5 × 1.75

= 8.75

So, C.S.A. = πrl

= 22/7 × 7 × 8.75

= 192.5

So, CSA of the cone is 192.5 cm^2