Q15 of 63 Page 21

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

We have,


Curved surface area of cone =πrl= 308 cm2


Slant height =l = 14cm


=× r × 14 = 308 = r = 7 cm


Total surface area = πrl+πr2=308 +×72


= 462 cm2


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