SSC CPO 2024 PYQ — Question 146

The correct answer is option 4 i.e. √7.

The slant height of a cone l = 4x

The height of a cone h= 3x

Radius r = $\sqrt{l^2-h^2}$

r = $\sqrt{(4x)^2-(3x)^2}$ = $\sqrt7$x

Curved surface area of cone = 4√7π 

⇒ πrl = 4√7π

⇒ $\sqrt7$x × 4x = 4√7

x = 1

Radius = $\sqrt7$x = $\sqrt7$