Question

3. The floor of a rectangular hall has a perimeter 250 m. If the cost of painting the four
walls at the rate of 10 per m’is* 15000, find the height of the hall.
[Hint: Area of the four walls =Lateral surface area.]​

Answer 1

Perimeter of rectangular hall = 2(l + b) = 250 m

Total cost of painting = Rs.15000

Rate per m^2 = Rs.10

Area of four walls = 2(l + b) h 

                               = (250×h) 

A.C.Q

(250×h)×10 = Rs.15000

⇒ 2500×h = Rs.15000 

⇒ h = 15000/2500 m

⇒ h = 6 m 

Thus the height of the hall is 6 m.