Q1 of 75 Page 221

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

Radius (r) of the base of cone =

= 5.25 cm


Slant height (l) of cone = 10 cm


CSA of cone = πrl


= * 5.25 * 10


= 22 * 0.75 * 10


= 165 cm2


Therefore, the curved surface area of the cone is 165 cm2


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