A solid cylinder has total surface area of 462 sq.cm. Its

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A solid cylinder has total surface area of 462 sq.cm. Its curved
surface area is 1/3rd of the total surface area. Then the radius of the cylinder is

Area of the curved surface =	1	× 462 = 154 sq.cm.
	3

∴ 2πrh + 2πr² = 462
⇒ 154 + 2πr² = 462
⇒ 2πr² = 462 – 154 = 308

⇒ r² =	308	=	308 × 7	= 49
	2π		2 × 22

⇒ r = √49 = 7 cm