12, The four walls of a room-6 m long, 3 mmbroad and 3.5 m high are to

1.	12, The four walls of a room-6 m long, 3 mmbroad and 3.5 m high are to be painted. Ifthe rate of painting is 650 per m2, find thetotal cost of painting.
Answer» Given,Length of wall l = 6m, Breadth b = 3m, Height h = 3.5m Area of four walls of room= 2(lh + bh) = 2(63.5 + 33.5)= 2(21 + 21/2)= 2(42 + 21)/2= 63 m^2 Therefore, total cost of painting = 63*650= Rs 40,950

12, The four walls of a room-6 m long, 3 mmbroad and 3.5 m high are to be painted. Ifthe rate of painting is 650 per m2, find thetotal cost of painting.

Answer»

Given,Length of wall l = 6m, Breadth b = 3m, Height h = 3.5m

Area of four walls of room= 2(l*h + b*h) = 2(6*3.5 + 3*3.5)= 2(21 + 21/2)= 2(42 + 21)/2= 63 m^2

Therefore, total cost of painting = 63*650= Rs 40,950