A room is measured as (9m × 8m × 6.5m). It has one door measuring (1.5m × 2m) and two windows, each of dimensions (0.75m × 2m). If the red color costs Rs.6.40 per square meter, then the cost of painting the wall red will be Rs.[[1]].

Question

A room is measured as (9m × 8m × 6.5m). It has one door measuring (1.5m × 2m) and two windows, each of dimensions (0.75m × 2m). If the red color costs Rs.6.40 per square meter, then the cost of painting the wall red will be Rs.[[1]].

Accepted Answer

A room is measured as (9m × 8m × 6.5m). It has one door measuring (1.5m × 2m) and two windows, each of dimensions (0.75m × 2m). If the red color costs Rs.6.40 per square meter, then the cost of painting the wall red will be Rs.1376.Given that,Length of a room is 9m, breadth is 8m and height is 6.5 m.We know that the area of the 4 walls can be calculated by multiplying the perimeter of the room by its height.Or we can say that, the area of the 4 walls is

2
    
     l+b
   ×h,
    where l is length, b is breadth, and h is height.Area of 4 walls is,

=2
      
       l+b
     ×h

=
      
       2
        
         9+8
       ×6.5
     
      m
      2

=
      
       2×17×6.5
     
      m
      2

=221 
      m
      2

Since the door and windows don’t need to be painted, we will have to subtract their area from total area.Area of the door and window,

Area of 1 door
     +
      
       area of 2 windows
     =
      
       2×1.5
     
      m
      2
     
     +
      
       2×2×0.75
     
      m
      2