Question

the curved surface area of a con whose slant height is 3times its radius (r) is given by

Answer 1

hello users ...

Solution:-
we know that:
curved surface Area of cone = πrl

where, r is the radius and l is the slant height.

According to given ;
slant height = 3 times of radius 

=> l = 3r 

=> C.S.Area of  cone = πrl 

= π * r * (3r)
= 3πr² Answer 

Here, option (4.) is correct

# hope it helps :)