Question

If a piece of cloth costs $₹10/m^2,$ then the total cost to build a square pyramid tent of base edge 10 m and slant height 10 m is .

• A. ₹ 1000
• B. ₹ 2000
• C. ₹ 3000
• D. ₹ 4000

Answer 1

The correct option is B ₹ 2000

Given:
$\text{Cost of the cloth}=₹10/m^2$
Base edge of square pyramid = 10 m
Slant height of square pyramid = 10 m

The amount of cloth required to build the pyramid will be the lateral surface area of the pyramid.

$\text{Lateral surface area of the square pyramid}$
$=4\times (\frac{1}{2}\times \text{base edge}\times \text{slant height})$

$=4\times \frac{1}{2}\times 10\times 10$

$=200m^2$

Hence, the total amount of money required
$=10\times 200=₹2000$