Question

the radius and slant height of a cone are in ratio 4:7. If its curved surface area is 792 cm²,find its radius

Answer 1

See the attached file

Answer 2

Answer:

Correct Question:-

The radius and slant height of a cone are in the ratio of 4:7. If its curved surface area is 792 cm²,find its radius?

Given that :-

• Ratio of radius and slant height = 4 : 7

Curved Surface Area = 792 cm²

To Find:-

• Radius of cone

$\boxed{Formula \:used :-}$

Curved surface area of cone = πrl

$\huge{\sf{\boxed{\boxed{Solution:-}}}}$

Let the radius of cone (r) = 4x cm

And the slant height of the cone (L) = 7x cm  

Curved surface area of cone = πrl

πrl = 792 cm²    

⇒ 22/7 × 4x × 7x = 792

⇒ x² = 792/22 × 4

⇒ x² = 9  

⇒ x = 3 cm

Radius of the cone = 4 × 3 = 12 cm

Hence,

Radius of cone is 12 cm.