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

Given :
Radius (r) of the base of cone = \(\frac{10.5}{2} cm = 5.25 \) cm
Slant height (l) of cone = 10 cm

We know that, CSA of cone
= \({\pi}rl\)
= [\(\frac{22}{7} × 5.25 × 10\) \({cm}^2\)]
= [\(22 × 0.75 × 10\) \({cm}^2\)]
= 165 \({cm}^2\)

Therefore, the curved surface area of the cone is 165 \({cm}^2\).