Find the area of the iron sheet required to prepare a

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Find the area of the iron sheet required to prepare a cone double the height of 12 cm with diameter of the base 14 cm. ?

1. 504 sq cm
2. 804 sq cm
3. 304 sq cm
4. 704 sq cm

Correct Option: D

r = Radius of the cone = 14/2 = 7 cm
h = Height of the cone = 12 x 2 = 24 cm
∴ Slant height (l) = √r² + h²
= √(7)² + (24)²
= √49 + 576
= √625
= 25 cm
Area of the sheet = Total surface area
= (πrl + πr²)
= πr(l + r)
= (22/7) x 7 x (25 + 7) = 704 sq cm