Question

The floor of a rectangular hall has a perimeter 250 m. If the cost of painting the four
walls at the rate of rupees 10 per m sq. is 15000, find the height of the hall.
(Hint: Area of the four walls = Lateral surface area.)​

Answer 1

Step-by-step explanation:

Let length, breadth and height of the hall be l, b and h respectively.

Perimeter of the floor of the hall = 2 (l + b) = 250 m.

Area of the four walls of the hall = 2h (l + b) ... (i)

Also, area of the four walls of the hall = 15000/ 10 m2 = 1500 m2 ... (ii)

From (i) and (ii),

we have 2h (l + b) = 1500 ⇒ h × 250 = 1500 [ 2(l + b) = 250] ⇒ h = 1500 /250 = 6

Hence, height of the hall is 6 m