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प्रश्न
Find the curved surface area of a cone, if its slant height is 60 cm and the radius of its base is 21 cm.
उत्तर
Given that
Radius of its base is 21cm
Slant height= 60cm
WKT, Curved surface area of a cone =`pirl`
∴ Curved surface area=`22/7xx21xx60`
=`3960cm^2`
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