Question

The floor of a rectangular hall has a perimeter $250m$. If the cost of painting the four walls at the rate of Rs. $10$ per $m^2$ is Rs. $15000$, find the height (in cm) of the hall.
(Hint: Area of the four walls = Lateral surface area)

Answer 1

Lateral surface area = (Perimeter of floor) $\times$ height

$=250h{m}^2$ and

cost $=$ Rate $\times$ area

$15000=10\times 250h$

$\frac{15000}{2500}=h$

$h=6m$