A class room is 7m long, 6.5m wide and 4m high. It has one door 3m X 1

1.	A class room is 7m long, 6.5m wide and 4m high. It has one door 3m X 1.4m and three windows measuring 2m x 1m.The interior walls are to be painted. Find the cost of painting atthe rate of Rs 3.50 per m2
Answer» Area of four walls of class= 2(lh + bh)= 2(74 + 6.54) = 2(28 +26)= 2(54) = 108 m^2 Area of window = 21 = 2 m^2 Area of door = 31.4 = 4.2 m^2 Area to be painted = 108 - 42 - 4.2= 108 - 12.2 = 95.8 m^2 Cost of painting= 95.83.50 = Rs 335.3

A class room is 7m long, 6.5m wide and 4m high. It has one door 3m X 1.4m and three windows measuring 2m x 1m.The interior walls are to be painted. Find the cost of painting atthe rate of Rs 3.50 per m2

Answer»

Area of four walls of class= 2(l*h + b*h)= 2(7*4 + 6.5*4) = 2(28 +26)= 2(54) = 108 m^2

Area of window = 2*1 = 2 m^2

Area of door = 3*1.4 = 4.2 m^2

Area to be painted = 108 - 4*2 - 4.2= 108 - 12.2 = 95.8 m^2

Cost of painting= 95.8*3.50 = Rs 335.3