Daniel is painting the walls and ceiling of a cuboidal hall with length, breadth and height of 15 m, 10 m and 7 m respectively. From each can of paint 100 m² of area is painted. How many cans of paint will she need to paint the room?

Area of Walls of a Room = 2 x h x (l + b)

= 2 x 7 x (15 + 10)

= 350 m²

Area of Roof = Area of Floor = 150 m²

Total Area to be painted = 350 + 150 = 500 m²

As, one can of paint is enough for 100 sq m

So, 500/100 = 5 cans are needed to paint the hall.