In Fig. 13.12, 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
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 = (
) cm = 10 cm
Cloth required for covering the lampshade = 2πrh
= 2 * 
* 10 * 35 cm2
= 2200 cm2
Hence, 2200 cm2 cloth will be required for covering the lampshade
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