How much cloth 2.5 m wide will be required to make a conical tent having base radius 7 m and height 24 m?

Question:

How much cloth 2.5 m wide will be required to make a conical tent having base radius 7 m and height 24 m?
(a) 120 m
(b) 180 m
(c) 220 m
(d) 550 m

Solution:

(c)  220 m
Let the length of the required cloth be L m and its breadth be B m.
Here, B = 2.5 m
Radius of the conical tent =7 m
Height of the tent = 24 m
Area of cloth required = curved surface area of the conical tent

$\Rightarrow L \times B=\pi \mathrm{rl}$

$\Rightarrow \mathrm{L} \times 2.5=\frac{22}{7} \times 7 \times \sqrt{7^{2}+24^{2}}$

$\Rightarrow 2.5 L=22 \times \sqrt{49+576}$

$\therefore L=\frac{22 \times 25}{2.5}=220 \mathrm{~m}$

Leave a comment

Close
faculty

Click here to get exam-ready with eSaral

For making your preparation journey smoother of JEE, NEET and Class 8 to 10, grab our app now.

Download Now