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प्रश्न
In the given figure, you see the frame of a lampshade. It is to be covered with a decorative cloth. The frame has a base diameter of 20 cm and height of 30 cm. A margin of 2.5 cm is to be given for folding it over the top and bottom of the frame. Find how much cloth is required for covering the lampshade.
`["Assume "pi=22/7]`
उत्तर
Height (h) of the frame of lampshade = (2.5 + 30 + 2.5) cm = 35 cm
Radius (r) of the circular end of the frame of lampshade = (20/2)cm = 10cm
Cloth required for covering the lampshade = 2πrh
`=(2xx22/7xx10xx35)cm^2`
= 2200 cm2
Hence, for covering the lampshade, 2200 cm2 cloth will be required.
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