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The lateral surface area of a hollow cylinder is 4224 cm^{2}. It is cut along its height and formed a rectangular sheet of width 33 cm. Find the perimeter of rectangular sheet?

Area of Rectangular Sheet = Surface Area of the Cylinder

Area of Rectangle = l x b

⇒ l x b = 4224

⇒ l x 33 = 4224

⇒ l = 128 cm

Perimeter of rectangular sheet = 2( l + b)

= 2 (128 + 33)

= 2 x 161 = 322 cm

Hence perimeter of rectangular sheet is 322 cm.

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A road roller takes 750 complete revolutions to move once over to level a road. Find the area of the road if the diameter of a road roller is 84 cm and length is 1 m.

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