Q : 2      The length, breadth and height of a room are \small 5\hspace {1mm}m, \small 4\hspace {1mm}m and \small 3\hspace {1mm}m respectively. Find the cost of white washing the walls of the room and the ceiling at the rate of \small Rs \hspace {1mm} 7.50   per \small m^2.

Answers (1)
N Nehul


Dimensions of the room = 5\ m\times4\ m\times3\ m

Required area to be whitewashed = Area of the walls + Area of the ceiling

2(lh+bh) + lb

\\ = 2(5\times4+4\times3)+ 5\times4 \\ = 2(32)+20 = 74\ m^2
Cost of white-washing per \small m^2 area = \small Rs \hspace {1mm} 7.50
Cost of white-washing 74\ m^2area = Rs (74 \times 7.50)
= Rs.\ 555

Therefore, the required cost of whitewashing the walls of the room and the ceiling is Rs.\ 555