Diameter of the base of a cone is 10.5 cm and its slant height is 10 cm. Find its curved surface area.

Given that, the diameter of the base of a cone, d = 10.5 cm
Slant height, l = 10 cm
To find out: Curved surface area of the cone.
r = d/2 = 10.5/2 = 5.25 cm
l = 10 cm
We know that, CSA of cone = πrl
=> (22/7) × 5.25 × 10 cm²
[∵ π = 22/7]
= 22 × 0.75 × 10 cm²
= 165 cm²
Hence, the curved surface area of the given cone is 165 cm².