Question

6. The floor of a rectangular hall has a perimeter 250 m and the cost of painting the four walls
at the rate of Rs. 5 per mºis 27000. Find the height of the hall.​

Answer 1

SOLUTION:-

Given:

The floor of a rectangular hall has a perimeter 250m & the cost of painting the four walls at rate of Rs.5/m² is 27000.

To find:

The height of the hall.

Explanation:

We have,

• Perimeter of the floor of hall=250m
• Cost of painting the four walls= Rs.27000.

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

•Area of four walls= 2(l+b)h

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

Perimeter of the floor of hall= 250m

Therefore,

2(l+b)=250m

Putting this value in the formula of area of four walls we get;

Area of four walls= 250h m².

Cost of painting per m² area= Rs.5

Cost of painting 250h m² area= Rs.(250h×5)

Cost of painting= Rs.1250h.

Now,

It is given that the cost of painting the walls is Rs.27000.

The height of the hall.

=) 27000 = 1250h

=) h= 2700/125

=) h= 21.6m