In the given figure, you see the frame of a lampshade.
Question. 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 $20 \mathrm{~cm}$ and height of $30 \mathrm{~cm}$. A margin of $2.5 \mathrm{~cm}$ 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. $\left[\right.$ Assume $\left.\pi=\frac{22}{7}\right]$

Solution:

Height $(h)$ of the frame of lampshade $=(2.5+30+2.5) \mathrm{cm}=35 \mathrm{~cm}$

Radius $(r)$ of the circular end of the frame of lampshade $=\left(\frac{20}{2}\right) \mathrm{cm}=10 \mathrm{~cm}$

Cloth required for covering the lampshade $=2 \pi r h$

$=\left(2 \times \frac{22}{7} \times 10 \times 35\right) \mathrm{cm}^{2}$

$=2200 \mathrm{~cm}^{2}$

Hence, for covering the lampshade, $2200 \mathrm{~cm}^{2}$ cloth will be required. [/question]
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