How many metres of cloth, 2.5 m wide, will be required to make a conical
Question:

How many metres of cloth, 2.5 m wide, will be required to make a conical tent whose base radius is 7 m and height 24 metres?

Solution:

Radius of the conical tent, r = 7 m
Height of the conical tent, = 24 m

Now, $l=\sqrt{r^{2}+h^{2}}$

$=\sqrt{49+576}$

$=\sqrt{625}$

$=25 \mathrm{~m}$

Curved surface area of the cone $=\pi r l$

$=\frac{22}{7} \times 7 \times 25$

$=550 \mathrm{~m}^{2}$

Here, area of the cloth $=$ curved surface area of the cone $=550 \mathrm{~m}^{2}$

Width of the cloth = 2.5 m

$\therefore$ Length of the cloth $=\frac{\text { area of the cloth }}{\text { width of the cloth }}=\frac{550}{2.5}=220 \mathrm{~m}$