A window frame 4 m long and 2 m wide is installed in a wall that has length 15 m and breadth 10 m. What will be the total cost of painting the wall if it costs Rs. 3.50 for 1 square metre?

This is the right answer because:- Length of the window frame = 4m Breadth of the window frame = 2m Area of the window frame = Length * Breadth = 4m * 2m => 8 square meters Length of the wall = 15 m Breadth of the wall = 10 m Area of the wall = Length * Breadth                      = 15 m * 10 m                      =>150 square meters Area to be painted = Area of wall -Area of window frame                                   = 150 sq. m - 8 sq.m                                  = 142 sq.m Cost of painting 1 sq. m = Rs. 3.50 Cost of painting 142 sq.m = Rs. 142 * 3.50                                                 => Rs.497

Ans. Rs. 497