Length of a rectangle is three times its breadth. Perimeter of the rectangle is 40cm. Find its length and width.
Given:
Length, l = 3 × Breadth, b
Perimeter of rectangle = 2 × (l + b)
2 × (3b + b) = 40
2 × 4b= 40
8b = 40
b = 5 cm
Length, l = 3 × 5
Length = 15 cm
Breadth = 5 cm