Question

The area of a floor of a rectangular room is 360m². If its length is 24cm, find its perimeter.

Answer 1

The area of a rectangle with length l and breadth b = A = l x b
Let the breadth of the rectangle = bcm
∴ For a rectangle with length 24cm and breadth bcm, A = 24 x b
⇒ 360 = 24b

⇒ b = `(360)/(24)`
= 15cm
The perimeter of a rectangle with length l and breadth b = P = 2(l + b)
∴  For a rectangle with length 24cm and breadth 15cm, P = 2(24 + 15) = 78cm.