Question

19. The area of four walls of a room is 120 m². If the length of the room is twice its breadth and
the height is 4 m, find the area of the floor.
​

Answer 1

Area of 4 walls ( LSA ) = 120 m²

Height = 4 m

area of ground = 120/4 = 30 m²

Answer 2

Given: area of four walls = 120m².

length= 2(breadth).

height= 4m.

Step-by-step explanation:

L.S.A. = Area of four walls = 2h (l+b) = 120m².

= 2 * 4 ( 2b + b) = 120

= 8 ( 3 b )= 120.

3b = 120/8 = 15

b = 15/3 = 5m.

now, l = 2b

l = 2x5 = 10m.

so, the area of floor = l * b = 5m * 10m = 50m².