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 metre square is rupees 15000find the length of the hall

Answer 1

2(l+b)=250
l+b= 125 m
cost =area/rate
15000= 2(l+b)h /10
150000/2=125×h
75000/125=h
h=600m

Answer 2

Step-by-step explanation:

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

Area of four walls = 2lh+2bh

= 2(l+b)h

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

= 250 m

Area of four walls = 2(l+b) h = 250h m2

Cost of painting per square meter area = Rs.10

Cost of painting 250h square meter area = Rs (250h×10) = Rs.2500h

However, it is given that the cost of paining the walls is Rs. 15000.

15000 = 2500h

Or h = 6

Therefore, the height of the hall is 6 m.