Curved surface area of a cone is 308 cm2 and its slant height is 14 cm. Find (i) radius of the base and (ii) total surface area of the cone


(i) Slant height (l) of cone = 14 cm

Let the radius of the circular end of the cone be r


CSA of cone = πrl


308 cm2 = * r * 14


r =


= 7 cm


Therefore, the radius of the circular end of the cone is 7 cm


(ii) Total surface area of cone = CSA of cone + Area of base


= πrl + πr2


= [308 + * (7)2] cm2


= (308 + 154) cm2


= 462 cm2


Therefore, the total surface area of the cone is 462 cm2


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