Question

The length, breadth, and height of a room are 5 m, 4 m and 3 m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate of Rs 7.50 m².

Answer 1

From given: 

Length = l = 5 m 

Breadth = b = 4 m 

Height = h = 3 m 

Total Area to be washed = lb + 2(l + b)h

Total area to be white washed = (5×4) + 2(5 + 4)3

= 20 + 54

= 74 

Total area to be white washed is 74 m² 

Now, cost of white washing 1 m² is Rs. 7.50 

Therefore, the cost of white washing 74 m² = (74 x 7.50) = Rs. 555