The curved surface area of a cone is 4070 cm2 and its diameter is 70 cm.What is the slant height ?(Use π=227).
Surface area of a cone=4070 cm2
Diameter of its base=70 cm
∴ Radius (r)=702=35 cm∴ Its slant height=Surface areaπr=4070×722×35=37 cm
Diameter of the base of a cone is 10.5 cm and its slant height is 10 cm. Find its curved surface area.