Q11 of 63 Page 21

A Joker’s cap is in the form of a right circular cone of base radius 7 cm and height 24 cm. Find the area of the sheet required to make 10 such caps.

We have,


Based radius of conical cap =r = 7cm


Vertical height = h = 24 cm


∴slant height = l === 25 cm


Required area of sheet =


= 10×πrl=10××7×25 cm2=5500 cm2


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