Q18 of 18 Page 13

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.

Base radius (r) = 7 cm
Height (h) = 24 cm
∴ Slant height (l) = = = = = 25 cm
∴ Curved surface area of a cap = πrl = = 550 cm2
∴ Curved surface area of 10 caps = 550 × 10 = 5500 cm2
Hence the area of the sheet required to make 10 such caps is 5500 cm2.

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