Question

Given below are the length and breadth of some rectangles. Find their perimeters.

(1) 9 cm, 6 cm
(2) 5.2 m, 4 m
(3) 7.5 cm, 3.2 cm

Answer 1

(1) Length of rectangle = l = 9 cm
Breadth of rectangle = b = 6 cm
Perimeter of a rectangle = 2 (l + b)
= 2 (9 cm + 6 cm)
= 2 (15 cm)
= (2 × 15) cm
= 30 cm
Thus, perimeter of rectangle = 30 cm

(2) Length of rectangle = l = 5.2 m
Breadth of rectangle = b = 4 m
Perimeter of a rectangle = 2 (l + b)
= 2 (5.2 m + 4 m)
= 2 (9.2 m)
= (2 × 9.2) m
= 18.4 m
Thus, perimeter of rectangle = 18.4 m

(3) Length of rectangle = l = 7.5 cm
Breadth of rectangle = b = 3.2 cm
Perimeter of a rectangle = 2 (l + b)
= 2 (7.5 cm + 3.2 cm)
= 2 (10.7 cm)
= 2 × 10.7 cm
= 21.4 cm
Thus, perimeter of rectangle = 21.4 cm