Question

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

Answer 1

area of 4 walls= 2(l+B)h
=54 m^2

area of ceiling=l*b
=20m^2

total area=74m^2

cost of white washing = 7.50*74
=555 rupees

Answer 2

Here is the required answer :

Given : Length 5m, Breadth 4m, Height 3m

Surface Area of the room = l×b + 2(bh+hl)

= 20 + 2(12+15)

= 20 + 2(27)

= 20 + 54

= 74m²

Now, Cost of white-washing per m² = Rs.7.5

So, the Total cost of white-washing

= Rs.(7.5×74)

= Rs.555

Hope It Helps ✌✌